Derived, screen by screen.

Derived is a training analysis app for iPhone and iPad. It reads years of workouts and daily health data from Apple Health, and from the files and training platforms you choose to connect, and shows how your HRV, resting heart rate and sleep move with the training you do.

Every number is computed on your device and comes with its sample size and its uncertainty. When there is not enough data for an answer, Derived says so and says how much more it needs.

Derived is not a medical device. It does not diagnose, treat or prevent any condition, and it gives no medical advice.

An iPhone with iOS 18 or later, or an iPad with iPadOS 18 or later, and data in Apple Health. Derived works with any amount of history, but its analyses compare days with each other, so it has more to say with months or years of Apple Watch data.

Some figures need a particular sensor: power-based load, critical power and the modeled W′ reserve need a power meter, and route and terrain figures need a recorded route.

Two short pages say what Derived does and where your data stays. The third, Connect Apple Health, opens Apple's permission sheet. It appears once and lists every type Derived reads or writes, and you choose what to share.

Derived then reads your history from Apple Health and asks once whether it may send notifications. You can use the app while it reads; the screens fill in as your history arrives.

It depends on how much history Apple Health holds. Years of workouts can take a few minutes, and a Live Activity on the Lock Screen shows the progress until it reads Apple Health is up to date.

After the first pass, Derived reads only what changed: each time you open it, and after a workout is saved to Apple Health when background sync is on (see Does Derived sync when it is closed?).

Apple shows its permission sheet once for each type, so later changes are made in the Health app: open Health, tap your picture or initials, tap Apps under Privacy, then tap Derived.

In Derived, Profile Integrations Apple Health shows how much data has arrived for each type and what Derived writes. Apple Health does not tell apps whether a read was refused, so a type with no data was either not recorded or not shared. Ask again appears there when there are types Derived has not asked for yet.

Only the types you approved, and only when you do something that calls for it:

• importing a recorded workout from a file
• changing your height or weight in Profile
• setting your FTP
• rating how hard a session felt (RPE)
• logging the carbohydrate you took in during a session
• saving the VO₂max Derived estimates from your rides

What Derived writes stays in Apple Health if you delete the app. You can remove it in the Health app.

English, French, German, Italian, Japanese, Polish and Spanish. Derived uses the language set for it in iOS Settings. Profile Settings Language shows the current one and opens the page where you change it.

The weekly summary written by Apple's on-device language model appears only when Derived runs in English.

Tap the person button at the top right of Today. The sheet is called Profile, because there is no account to configure. From the top:

• About you: your sex, age, height and weight
• Training profile: your thresholds, estimates and model inputs
• Your data: Integrations, Privacy and data, Devices and Derived Pro
• App: Today screen and Settings
• at the bottom, Methodology and Open-source licenses

The info button i opens a short note on that figure: what it is, how it is computed and how to read it, often with a small diagram.

A result in Findings opens a fuller page, How this was computed, with the method, its inputs, the number of days behind the result and its interval. Read the method note leads to the method's entry in the method catalog.

Findings has a search field at the top. Type a metric, such as HRV, sleep or load, and it opens that metric's entry: its chart and everything found about it. It offers only entries that exist in your data, so a word with no entry lists the entries you have.

Yes. Say, for example, "Show today in Derived", "Show my workouts in Derived", "Show my metrics in Derived", "What does my data say in Derived" or "Simulate a race in Derived". In the Shortcuts app, the Open Derived screen action opens Today, Calendar, Metrics, Findings or Simulate.

Yes, the Derived widget, in small, medium and large sizes on the Home Screen and as a Lock Screen widget. Edit the widget to choose what it shows:

• Health: resting heart rate, HRV, sleep and VO₂max with more load. Series picks which one, or Clearest answer.
• Where you are: fitness, fatigue and form.
• Next race: the projected time, recomputed each day.

Tapping the widget opens the screen it comes from.

Only the kinds you turn on in Profile Settings Notifications:

• New workouts, when workouts arrive from Apple Health or Strava
• New records, when a workout sets an all-time best
• Metrics, when new workouts change your fitness, fatigue and form
• Thresholds to confirm, when your workouts point to a new threshold such as FTP
• New readings, when a new resting heart rate, VO₂max or weight arrives

Derived makes these notifications on your device from your own data. None come from a server, and none appear while Derived is open. Badge on the app icon counts the thresholds and readings waiting for you.

Up to three results from Findings that hold up after correction for multiple comparisons, the most informative first. Tap one to open what it is about. When nothing is decided yet, the card says so. All findings opens the Findings tab.

When new data changes what the results rest on, the card shows Updating the findings… and the new results replace the old ones together.

Under Findings, on days with a session. Each card opens the workout. On a day without one, the section does not appear. Every other day is in Calendar.

Training load, Form, HRV, Resting HR, Sleep, VO₂max, Max HR, FTP, Steps, Active energy, Exercise minutes, Walk + run, Cycling, This week, Planned, Similar days and Fueling. Each appears once you have data for it.

Tap a chart to open its full history. The info button on a body signal explains how a value is read against your usual. If FTP or Max HR is not set, its card offers the value detected from your workouts or lets you enter your own.

Tap Customize at the bottom of Today, or open Profile Today screen, and turn off the charts you don't want. Show every chart again brings them all back.

Derived does not combine your signals into one score. Each signal is shown on its own, against your own usual and with its typical spread, so you can see which one moved and by how much. No value is labeled good or bad.

Your week so far: days trained, total load and how it compares with last week, with your median HRV and resting heart rate.

When Derived runs in English and Apple Intelligence is available, Apple's on-device language model writes it as a short paragraph from these numbers. It never computes a number itself, and without it you read the same figures as plain sentences.

The next three events on your calendar, such as a race or a trip, with their dates, and a line on where your form is heading.

Past days whose signals most resemble today, each listed with its HRV, resting heart rate and sleep.

After a ride or run of two hours or more, the Fueling card asks how much carbohydrate you took in during it. It asks only about sessions from the past week whose recording is complete enough to analyze, and never about a race.

• Log fueling records the grams you took in.
• I ate nothing records a real zero.
• Dismiss leaves the session without an answer.

A zero and a missing answer mean different things to the analysis, so they are kept apart. Logged carbohydrate is saved to Apple Health across the session's time. Derived records what you consumed and sets no intake target.

The column in each day rises with that day's load. Full height is one of your own heaviest recent days, so a heavy day reads as heavy whatever your volume, and the column's color steps up with it. A day with more than one session splits its column into blocks; a day without a session has no column. The scale comes from your training days of the last 90 days.

The info button at the end of the month row explains the marks for planned workouts and events.

The week's number and dates, its total load, and your form at the end of the week. Tap the header to open Fitness and fatigue, a chart that starts at that week.

A mark beside the figures means your fitness rose more that week than a common rule of thumb; tap it to read the figure and the convention it is compared with. Weeks still to come show where form is heading if nothing is trained, marked as projected.

When the current week is off screen, a Today button appears in the month row. Tap it.

A sheet for that day, with:

• its load and form, each with an info button, and fitness against fatigue
• the day's events
• Workouts: the sessions you recorded and any planned workouts
• Health that day: HRV, resting heart rate and sleep, each marked lower, usual or higher against the 60 days before
• Add to this day, for an event or a workout

Tap the + button at the top of Calendar and choose Event, or open a day and tap Add to this day. Choose the kind: Race, Illness, Injury, Travel, Altitude or Something else.

A race takes a discipline and a name. The other kinds take a note, and illness, injury, travel and altitude can run from a first day to a last day. To change or remove an event, tap it in the day's sheet.

Marked days change what the analysis reads:

• Days of illness or injury are left out of Findings and of the days the road to race day is drawn from, and Findings shows how long coming back took.
• An altitude camp gets its own reading in Findings, and its days stay out of the heat findings.
• Races let Findings show the weeks before your past races, once three of a discipline are marked.
• Every event appears as a marker on your metric charts, to explain a change.

Open the workout, turn on Race near the bottom of the screen and choose its discipline. This adds a race on that day to your calendar.

Tap the + button at the top of Calendar, choose Workout, then Build a workout. Add the steps in the order you will do them, with targets taken from your thresholds. Steps can repeat, and a ramp can be built in steps. Add to calendar puts the workout on the day you chose.

Derived does not suggest steps, targets or days. The workout is yours.

Yes. Open the planned workout from its day:

• Send to Apple Watch hands it to your watch through the system's own preview. It is available on iPhone.
• Send to Intervals.icu and Send to Wahoo appear once you turn on sending plans to that service (see Does Derived send anything to a platform?). Sending again replaces what the service holds.
• Edit workout changes it, and Remove from calendar deletes the plan. Every session recorded on that day stays.

Tap the + button at the top of Calendar, choose Workout, then Choose File. The same form is in Profile Integrations Import workout. Derived reads the file and shows what it found before anything is saved.

• A recording of a session goes to Apple Health with the rest of your sessions. Only values present in the file are added.
• A structured workout goes on the calendar on the day you choose, and nothing from it goes to Apple Health.

A GPX file needs timestamps to count as a recording.

Derived recognizes it and offers Add missing data. This adds any channels or route the file has and the recorded workout lacks. Nothing already there is replaced or counted twice.

When a session matches a plan, its card in the day's sheet carries the plan's mark, and the workout opens with a Plan section: what was planned, and how it went. From there you can link another plan or unlink this one.

Tap the chart, or drag sideways along it; dragging up or down still scrolls the page. The reading appears in a row above the chart, so the chart itself stays still, and tapping the reading again clears it.

Choose the channel above the chart, and switch the horizontal axis between Time and Distance.

Tap Select span, then drag across the chart. The span applies to every section below, so zones, splits and the other figures describe that part only. Whole workout brings back the full session.

Tap Compare channels under the chart. Workout data opens in landscape, with each channel in its own lane and one cursor across all of them. If your iPhone is locked in portrait, Derived asks you to turn the screen.

Each section answers one question, and only the sections your data supports appear. The order adapts to the session: a linked plan puts Plan first, a new record moves Records up, and detected intervals move Reps up.

Modeled reserve follows your W′ through a session with power, using your critical power and W′. Data lists the channels recorded and where data is missing.

Derived computes a figure only when the data meets its conditions, and leaves it out otherwise. Weighted power, for example, needs a power recording with no more than 5% of it missing. An average of what is there would be off by several percent without saying so, so Derived shows nothing instead.

The Data section lists what was recorded and what is missing. On every chart, missing data is drawn as a gap.

The first way its data allows: a ride by power against your FTP, a run by grade-adjusted pace against your critical speed, any session by heart rate against your threshold heart rate, then by your RPE, and otherwise by its duration. The first four are scaled so an hour at threshold comes to 100. The Load section names the method used.

More in What is session load?

Near the bottom of the workout, RPE takes a rating of perceived exertion from 1 to 10, with a word beside each number as a guide. Derived saves the rating to Apple Health with the time you gave it.

A rating sets a session's load only when nothing measured can: power, pace and heart rate come first.

Yes, under Note near the bottom of the workout. Your note stays on this device and leaves it only in an export you start.

Tap Sessions like this, under the route map. It lists sessions of the same sport with a similar duration and load, newest first, and shows where this one sits among them. Change criteria sets how close the duration and load must be.

Tap the route map, then Explore route for the map and the elevation profile. Drag along the profile to inspect any point.

Yes. When a connected platform holds the same activity with channels the workout lacks, such as power, cadence, speed or the route, the top of the workout says so and offers Import workout data. If more than one platform has it, choose one with Import from and the platform's name.

Open Export near the bottom of the workout, tap Export file, choose a format, then choose where the file goes.

• FIT: every recorded channel, for training apps.
• GPX: route, heart rate and cadence, for maps and route planners.
• TCX: most channels, for apps that do not read FIT.
• CSV: one row per sample with its source, for a spreadsheet.

The file holds this session only: its samples, its route if it has one, and where the numbers came from. No daily health data goes with it.

Tap Share summary. Choose what the picture leads with, up to six figures and a background, then tap Share image. You see exactly what leaves your phone before it does.

From the workout itself, when its source recorded it. For an outdoor workout without one, Derived can ask Apple Weather, on request, for the conditions at its start. It sends the start location rounded to about a kilometer and the hour. Indoor workouts get no outdoor weather.

This week's load against your usual week, which is the median of the eight weeks before; where your fitness, fatigue and form stand, with arrows for the way each moved over the last seven days; and how far your fitness moved in that week. Tap it to see fitness and fatigue over time.

None of these has a good or bad zone. They describe where you are against your own past.

Your load, HRV, resting heart rate and sleep on one time axis, so a day reads straight down. Load shows each day's session load, with fitness as a line and fatigue dashed. HRV and resting heart rate are drawn against your usual, the median of the 60 days before each day, in MAD, the typical spread around it. The shaded band is one MAD either side.

A gap is a day without a reading; nothing is filled in. Dashed vertical lines are events you added. Tap the card to open the full chart.

All metrics groups the charts into four categories. For example:

• Activity: steps, active and resting energy, exercise minutes, and walking, running, cycling and swimming distance.
• Cardio: VO₂max and the share of time in each heart-rate zone, also split by discipline.
• Training: daily and weekly load, monotony, intensity distribution, session intensity, fitness and fatigue, form, load mix, power curve, critical power, best efforts, power and pace zones, cadence and running power.
• Recovery: HRV, resting heart rate, sleep and data coverage.

A chart appears only when you have data for it, so there are no empty charts.

Open the metric and choose a window at the top: 1W, 1M, 3M or 1Y. Swipe the chart to move through time, or touch and hold it to read a day.

Under the chart, the overview shows up to a year with your window marked; tap or drag it to move. With more than a year of history, the strip of years below picks which year the overview shows.

For the days on screen, or for a span you selected on the chart: the average or the total, the highest and lowest value, the change from first to last, and the number of days with a reading. Clear selection returns to the visible range.

Everything Findings knows about the metric: each relation in which it is the outcome, with its interval and the number of days behind it, and how it behaves in the week after your hardest days. Tap a relation for the full result and how it was computed.

On the training load chart, the same place shows What load moves and In heavy training blocks.

In Metrics under Training, on the Critical power card, and in Profile Training profile. Both are estimated from your own maximal efforts and shown with their 95% intervals and the number of sessions they rest on. Until there are enough efforts, the card says so: a few hard efforts of 2 to 15 minutes let the model fit them.

The analysis window: the days Findings reads. When you choose a window other than All in Findings, a badge with its dates appears over Calendar and Metrics, and days outside it are dimmed in the calendar. Tap Clear on the badge to read all your days again.

How many relations Derived checked in the days it read, and how many of them held up after correction for checking that many at once. The info button beside it explains n, the number of days a result rests on.

Choose under Days read: 90 days, 6 months, 1 year, All, or Custom, where Edit dates sets your own range. A relation needs 90 days with data, so a shorter selection reads the 90 days that end with it.

Days marked as illness or injury are left out, and the number of days left out appears under the dates. The same window applies to the findings on Today, to Calendar and to Metrics.

Each row sets your daily load against one metric, over the same day and the week after. The dot shows how closely the two move together, from −1 to 1, at the day where they move most, and the bar is its 95% interval. Left of the center line, the metric is lower with more load; right of it, higher.

A bar that crosses the center line is no clear link, and that is an answer too. Tap a row to open the metric with everything found about it.

The same metrics, compared between stretches of high and low weekly load. A block lasts at least 14 days, and high or low is judged against the median of the 12 weeks before it. The difference is measured with Cliff's delta, with its 95% interval.

A hard day is a training day in the top quarter of your own training days by load. The path is the median distance from your usual on each of the seven days after one, using only hard days with no other hard day in the week after them, so two sessions never stack into one curve.

The share counts how often the next day moved the expected way and sets it against days picked at random. A recovery time is stated only when that share holds up and the path returns within the week.

Whether HRV, resting heart rate and sleep follow one straight line against your weekly load, or bend at some level. Weekly load for a day is the load of the seven days before it. The bar marks where the line turns, with its 95% interval, on the range of your weekly loads, and the three signals are corrected together.

It needs 180 days of data across at least three load levels. If the interval spans more than 40% of your weekly loads, no bend is located. A bend describes your recorded range; it is not a training instruction.

It appears once a race in the future is on your calendar. For each day from three weeks before your past races to a week after them, it shows the median of your load, HRV, resting heart rate and sleep across those races, with a 95% interval. It needs three past races, of the same discipline when your next race has one. Three to five races describe what happened before them and are too few for a verdict.

Simulate this race opens the race in Simulate.

Three readings against temperature, each on its own:

• heart rate at the same power, on outdoor rides
• decoupling: how far power drifts from heart rate within a steady ride
• your HRV the next morning, after a day with an outdoor workout of 45 minutes or more

Only a temperature recorded with the workout, or fetched from Apple Weather for it on request, is used. Indoor workouts and the days of a marked altitude camp are left out, and humidity and heat acclimation are not in the model. Until your rides show an effect, Simulate uses a published range for heat.

Derived looks for breaks of three days or more without a workout while your resting heart rate and HRV were both away from your usual, and lists them under Breaks you might want to mark. What was it? lets you mark one as Illness, Injury or Travel, or choose Nothing to mark.

A marked break is left out of the other findings, as any marked illness or injury is.

For each illness or injury you marked: how many days it took, counted from the day after its last marked day, until your resting heart rate, HRV and nightly wrist temperature were each back within their usual band for two days running. Each episode is read on its own, and nothing is averaged.

These describe your own past episodes. They say nothing about when to train.

Once you have marked three illnesses, or three injuries, Derived shows your load and recovery signals from the first day of each episode, as the median with its 95% interval. A few episodes show what happened around them; they do not make a rule.

Each camp you marked as Altitude, on its own: resting heart rate and HRV at altitude and after it, heart rate at the same power on the camp's rides, and fitness before the camp and on its last day, all against your usual from the 60 days before it. A camp is also a training block, and these readings cannot tell altitude and training apart.

Each calendar year's median HRV, resting heart rate and sleep in their own units, with 95% intervals, and under them the year's total load and its days of illness or injury. It needs two seasons with 200 measured days each.

The interval includes zero after correction: in your data, the two measures do not move together clearly enough to call it a link. It is a real answer and is shown with the same weight as a found one. A result still waiting for data says how many more days it needs instead.

No. A finding describes how two measures moved together in your own history. Something you did not record can move both, so Derived does not claim a cause, does not diagnose anything and does not tell you how to train.

Relations need 90 days with both training and health data, and some readings need more: the bend in weekly load needs 180 days, seasons need two years with 200 measured days each, and race paths need three past races. Until then, Findings says it is reading your history, or that findings appear once a few weeks of paired training and health days are in.

Next race counts down to your next planned race and shows its projected time with its range, the change since a week earlier and how the projection moved day by day. Below it are Races ahead, Past races, Route library and Ledger, which shows how past predictions held up.

Tap Plan a race and choose what you are racing: Ride, Run, Swim or Triathlon.

• A ride or a run starts from a course: from your library, your own rides or runs, a connected service, or a GPX file.
• A swim takes a distance and a venue, pool or open water.
• A triathlon takes a distance (Sprint, Standard, Middle or Long) and its bike and run courses.

A race already on your calendar opens in Simulate from Simulate this race, on the event or in Findings.

For a ride:

• Course draws the elevation over your modeled W′ reserve and marks its lowest point.
• Climbs lists each climb with its power, speed, time and the W′ left at the top.
• Splits takes the ride stretch by stretch between climbs, when the course has climbs to split it at.
• Race holds the race's day, the road to race day and the plan's actions.

A run has Course, Climbs and Race. A swim has Swim and Race. A triathlon has Splits, leg by leg, then Bike, Run and Race.

For a ride, the tray at the bottom of the screen, Your plan, holds the controls in groups:

• Power: the power you plan to ride, between climbs when the course has them, and the pacing, including W′ on climbs with the W′ to keep at each top.
• Weight: your weight, from Apple Health or set by you.
• Bike: bike and kit, drag area (CdA) and rolling resistance (Crr).
• Weather: temperature, and wind as a headwind or a tailwind.
• Fuel: the carbohydrate you take in, for rides projected to last two hours or more.

A triathlon adds Swim and Transitions. There is no button to run the model: each change recomputes the time, and the figure at the top shows how much the last change moved it. A run is projected from your critical speed and D′ and has no tray.

Your critical power and W′ come from your own best efforts. The course is computed segment by segment from a published equation for gravity, rolling resistance and air, and your W′ is spent and recovered along the way.

Values your data cannot measure, such as drag area and rolling resistance, start from population priors marked Prior until you set your own, and Profile Model inputs lists them. They configure the model and do not compare or grade you. Heat uses your own rides once they show an effect, and a published range from two laboratory time trials until then.

Derived runs the projection many times, each time drawing your parameters from their uncertainty. The range is where the finish time fell in 80% of those runs: one run in ten came out faster than P10 and one in ten slower than P90. The middle figure is the median.

On the Race view, Save as race puts the race on your calendar on its day. Its projection is then recomputed every day, and the widget can follow it.

For a ride or a run, Freeze this prediction keeps the projection exactly as it is. After the race, open the prediction in the Ledger and add your actual time to score it.

Every prediction you froze and, under Calibration, how the scored ones held up:

• P10–P90 coverage: the share of actual times that fell inside the predicted range. A well-calibrated range holds about 80%.
• Mean pinball loss: the average miss, weighted by which side of the range it fell on. Lower is closer.
• Scored predictions: how many have an actual time.

With fewer than five scored predictions, coverage says little either way.

On the Race view: where your fitness, fatigue and form would stand on race morning in this scenario, each with its P10–P90 range and today's value, and the load each week holds on the way.

The days ahead are drawn from your last six weeks of training, with a taper before the race based on a published meta-analysis of tapering. Days marked as illness or injury are left out of the weeks they are drawn from.

Your routes from your rides, the services you connect and GPX files, each with the rides you did on it. A row shows the profile's outline, the name, the distance, the climbing and the number of rides. Add routes brings in more, and touching and holding a route lets you delete it. A route you rode twice or more can set those rides side by side.

No. It projects the consequences of the plan you wrote, with its uncertainty. It does not judge whether a plan is safe or wise, and it does not tell you how to race.

From Apple Health. About you shows your sex and age, which change only in the Health app, and your height and weight, which you can change here. A change to your height or weight is saved to Apple Health.

In Profile Training profile, the thresholds card holds Threshold power (FTP), Threshold heart rate, Maximum heart rate and Critical speed, each with the date it applies from and the zones it sets. Tap one to open its page:

• Detected from your workouts shows the value Derived sees in your training. Use adds it from today; workouts before today keep the value of their day.
• History lists every dated entry, and Add entry sets one yourself.

A workout is always read against the value in effect on its day.

It works your thresholds and estimates out again from your workouts. Thresholds back in time sets FTP, maximum and threshold heart rate and critical speed for every past day. Estimates as of today fits critical power and W′, VO₂max, D′ and the run–walk transition again.

A day with no value takes the new one at once. A day that already holds a different value waits under Already set on that day, where you keep it or replace it. Each threshold's page can also recalculate that threshold alone.

Critical power with W′, VO₂max, D′ and the run–walk transition, estimated from your workouts. Each shows a range, its 95% interval, and n, the number of your efforts it rests on. Without enough efforts it reads Not estimated.

The VO₂max page shows the value estimated from your rides next to the one in Apple Health, and Save to Apple Health writes yours there.

In Profile Settings Units. Distance, elevation, temperature and swimming units are set separately; speed, pace and splits follow distance. Until you choose, each unit follows your iPhone's region, and weight and height follow the Health app. Your data is kept in metric units, so this changes only what you see.

Yes, in Profile Settings Appearance: System, Light or Dark. System follows your device, including a light and dark schedule if you set one.

With Sync in the background on, in Profile Settings Background activity, iOS wakes Derived after a workout is saved to Apple Health, at most once an hour, and now and then on its own schedule. Strava is included when its automatic sync is on.

iOS decides when background work runs, and Background App Refresh and Low Power Mode both affect it. With the setting off, Derived syncs when you open it.

On iPhone, Profile Settings Haptics turns off every haptic Derived plays on charts, controls and tabs. Controls drawn by iOS follow your iPhone's own setting.

Yes. In Profile Settings, the lock row is named for what your device has: Face ID, Touch ID, Optic ID or Passcode. With the lock on, Derived checks it is you when it opens and when you come back to it, and keeps your data out of the app switcher. Your device passcode works as well.

Lock again sets how long Derived can stay in the background before it checks again: Immediately, After 1 minute, After 15 minutes or After 1 hour. Widgets and notifications are outside the lock.

Profile Methodology opens the method catalog: every method Derived runs, each with a note on what it measures, what it cannot tell you and an example, along with its version, the number of comparisons in its family and the seed that makes its random draws repeatable. Beside each figure in the app, the info button explains that figure.

Intervals.icu, Polar, Strava and Wahoo, in Profile Integrations. Tap the platform, tap Connect, and sign in on the platform's own page, where you choose what to share. The tokens that keep the connection open stay in your device's Keychain.

Your activities, with every channel the platform holds. The platform's screen lists them: Import brings one in, and Imported or In library marks what is already here. You can bring in your full history; keep Derived open while it runs.

Sync new activities automatically brings in new ones as they appear, and Save as route adds an activity's course to your route library.

Intervals.icu and Polar can, once you turn on Sync health data on the platform's screen. Resting heart rate and sleep from Intervals.icu, and sleep from the last 28 days from Polar, fill the days Apple Health has no reading for.

A day keeps one value from one source, with Apple Health first, so a reading that reaches Derived through several services counts once. Nothing from a platform is written to Apple Health. Wahoo shares sessions only.

Derived matches sessions that arrive from more than one source. When the platform's copy has channels the Apple Health copy lacks, the workout offers Import workout data. When Derived cannot tell whether two sessions are the same, it shows them in Profile Privacy and data and leaves the decision to you.

Only planned workouts, and only when you ask. Turn on Send plans to Intervals.icu or Send plans to Wahoo in Profile Privacy and data Sending to a service; a planned workout's screen then offers that service next to Apple Watch. If you connected before turning it on, Connect again grants permission to write.

Strava and Polar take no planned workouts. Derived sends no recorded sessions to a platform; to move one, export it as a file.

Open it in Profile Integrations and tap Disconnect. This ends the connection on your device and asks the platform to withdraw Derived's access.

What it brought in stays. To remove that too, use Data sources in Profile Privacy and data. Removing a source's data keeps the sessions and everything in Apple Health.

No. The platforms require an app secret when a sign-in is exchanged for a token, and that secret cannot live inside an app. That exchange, and the renewal of an expired token, passes through a small service at api.getderived.com. It stores nothing and keeps no logs, and your activities and health data never pass through it.

Yes, with the same five tabs. It reads Apple Health on the iPad, which holds the history your iPhone and Apple Watch record when Health is turned on in iCloud, and computes everything on the iPad.

What you make in Derived, such as notes, thresholds, events, plans and routes, stays on the device where you make it; a backup moves it between devices. iPad has no Haptics setting, and only iPhone sends workouts to Apple Watch.

It pairs once with your iPhone and keeps a read-only copy of your data, which the iPhone updates over your own network while Derived is open on it. It shows Overview, Workouts and iPhone. Nothing you do on the Mac changes your data on the iPhone. The Mac app comes with every Derived subscription.

1. Open Derived on the Mac. It shows a pairing code.
2. On your iPhone, open Profile Devices Pair and sync and tap Scan pairing code.
3. Point the camera at the code. It changes every two minutes and works once.

Without the camera, choose your Mac under Nearby, check that both screens show the same six digits, and confirm with Codes match.

On your iPhone, Unpair in Profile Devices Pair and sync deletes the shared key from the iPhone's Keychain. On the Mac, Unpair and remove this copy deletes the Mac's copy. To mirror again, pair again.

A tier for coaches, coming in December 2026: a coach console on Mac, where each athlete shares an encrypted, read-only copy they sign and can revoke at any time. In the app it shows as Available soon.

On your iPhone or iPad. Derived has no account, no telemetry and no cloud upload, and its App Store privacy label is Data Not Collected. Your data is mirrored only to devices you pair, in sessions you approve. Anything Derived writes to Apple Health takes part in your own Health sync, which Derived neither uses nor controls.

The privacy policy has the details.

Not for your data. Your device's own backup, in iCloud or on your computer, may include the app's data, as Apple handles it under your settings.

No. Apple's on-device language model writes it on your device from numbers Derived has already computed.

In Profile Privacy and data, tap Export backup. The backup holds what you made in Derived: notes on your sessions, thresholds, events, routes, plans, fueling and predictions. It holds nothing that Apple Health keeps; sessions, their samples and daily values come back from Health.

The backup is a Derived file, which only Derived opens. Saved backups lists each one with its date, time and size, and Share backup sends it where you want, such as Files.

Tap Import backup in Privacy and data, or open the backup file from Files, Mail or AirDrop. Before it runs, Derived says what it adds: thresholds, events, routes, plans, fueling and predictions the device does not have, and notes for sessions that have none. Nothing is replaced or removed.

Sessions that are not yet in Apple Health on this device are counted; import the file again once Apple Health has them.

Yes, one session at a time, as FIT, GPX, TCX or CSV, from the Export section of a workout (see How do I export a workout as a file?). The backup has a different job: it moves what you made in Derived between your devices.

Yes. Data sources in Privacy and data lists what each source brought into Derived. Removing a source's data keeps the sessions and everything in Apple Health.

Under Maintenance in Privacy and data, it rebuilds every derived figure from what is already on your device. It fetches nothing.

Delete all app data, at the bottom of Privacy and data, removes Derived's own copy: imported daily values, workouts, events, settings, fueling entries, predictions, analysis history and profile facts. It also unpairs your devices. If you have saved backups, you choose whether they stay or go.

It cannot remove anything from Apple Health or from a platform you connected; remove that in the Health app or on the platform. Deleting the app deletes its data from the device.

€79.99 a year, €24.99 for three months or €9.99 a month. Each opens every screen and every analysis on iPhone and iPad, and the Mac companion app from November 2026. Prices are in euros; the App Store shows them in your local currency.

No. Derived is one subscription that opens everything.

Your data stays on your devices, and everything opens again when you subscribe again. What Derived wrote to Apple Health stays in Apple Health.

In your Apple Account settings. The subscription renews automatically unless you turn it off at least 24 hours before the end of the current period.

No. The subscription covers Derived on iPhone and iPad and the Mac companion app. Derived Pro, for coaches, follows in December 2026 as a higher tier.

A session's load is computed the first way its data allows:

1. a ride by power, against your FTP
2. a run by grade-adjusted pace, against your critical speed
3. any session by heart rate, against your threshold heart rate
4. by your rating of perceived exertion (RPE)
5. otherwise by its duration, adjusted for the kind of activity

The first four are scaled so an hour at threshold comes to 100. A day's load is its sessions added up; on a day with no workout, the exercise minutes Apple Health recorded count at half.

The methods are close but not the same, so a session's load can change when the threshold it is read against is set, or when its heart rate or power arrives.

Fitness is your daily load averaged over about six weeks, and fatigue the same over about a week, both weighted toward recent days. Form is fitness minus fatigue at the end of the day before. Below zero, your recent days carried more load than your six-week average; above zero, less. A rest day counts as zero load.

The word beside form names its band: transition, fresh, neutral, building or strained, from the highest down. None of them is good or bad. In the first six weeks of a record the averages have too little behind them, so the figures show as dashes.

Fitness and fatigue are exponentially weighted averages with time constants of 42 and 7 days, the structure of Banister's impulse-response model.

Your usual is the median of your earlier days: for a daily reading, the 60 days before it. MAD, the median absolute deviation, is how far those days typically sit from it. +1.0 MAD means a day one typical spread above your usual; −2.0 MAD, two below.

One unusual day barely moves either figure, which is why they are used instead of the average and the standard deviation. Where a shaded band is drawn, it spans one MAD either side of your usual. Until there are enough earlier days with a reading, no comparison is shown.

n is the number of independent days a result rests on. Days next to each other tend to look alike, so a run of similar days counts for less than the same number of unrelated ones; n is the count after that allowance, and raw is every day that went in.

The 95% interval is the range of values your data supports for the result. A small n widens it, and the width of the interval is the honest measure of how sure a result is. For an estimate such as critical power, n is the number of your efforts it is fitted to.

Findings checks many relations at once, and some would look like links by chance alone. Each relation has to hold up after a correction for the number checked before it counts as found. Derived controls the false discovery rate with the Benjamini–Hochberg procedure at 10% within each family of checks, and the method catalog shows the size of each family.

Weighted power gives hard surges more weight than a plain average does: it is the fourth root of the mean of the fourth power of your 30-second rolling power. Intensity ratio is weighted power divided by your FTP. Both need a power recording with no more than 5% missing.

Critical power is the boundary between the power you can sustain for a long time and the power that draws on a limited reserve. W′ is the size of that reserve: the work you can do above critical power. Derived estimates both from your own maximal efforts of about 2 to 15 minutes and shows them with their 95% intervals.

The modeled reserve, or W′ balance, follows that reserve through a session with power: it falls while you ride above critical power and recovers below it. For running, critical speed and D′ play the same roles, and for swimming, critical swim speed.

Apple Watch estimates VO₂max and saves it to Apple Health, and Derived estimates its own from your critical power and W′ and your latest weight. The VO₂max page in your training profile shows both, and Save to Apple Health writes Derived's estimate there.

How far power, or pace, and heart rate drift apart over a steady session: the ratio of output to heart rate in the first half compared with the second half. Derived reads it only from steady sessions, since intervals have no single drift to measure.

A projection is the time Simulate computes for a plan now; it changes as your data and the plan change. A prediction is a projection you froze: it stays as it was and is scored against your actual time in the Ledger.

Derived has nothing from Apple Health yet: access was not granted, or Health returned no workouts or recovery data for the recent period. Check access in the Health app (your picture or initials, then Apps under Privacy, then Derived), then tap Import again.

Pull down on Today to read Apple Health again. If the workout is not in the Health app, Derived cannot read it: check the app that recorded it, sync the platform it is on, or import its file. With background sync on, new workouts arrive without opening Derived, at most once an hour.

There is not enough data behind it yet. Fitness, fatigue and form need about six weeks of record, for example, and a reading against your usual needs earlier days with data. A dash means there is no value yet.

This happens after you set a threshold, after heart rate or power arrives for a session, or after you rate a session. Each workout is read against the thresholds in effect on its day. See What is session load?

Findings needs months of days with both training and health data. See Why does Findings show so little?

Check Profile Settings Notifications: the permission, and the kinds turned on. Derived does not notify you while it is open. Open iOS Settings leads to the system setting.

The Mac updates while Derived is open on your iPhone and both are on the same network. In Profile Devices Pair and sync, Not nearby means the iPhone cannot see the Mac right now, and Sync now starts an update when it can.

Allow camera access for Derived in iOS Settings, then tap Scan again. Without the camera, pair through Nearby and compare the six digits.