Devices and connections

What you can connect#

The older Fitbit Web API connection has ended (see Fitbit and Pixel Watch). Apple Health is not a source. Brands without an integration, such as WHOOP, Suunto and Amazfit, cannot be connected directly. If you wear one, the Connect page offers “My device is not here” and a list of names to tap, which only tells us what people want. The Supported devices page on our website lists the models we know of, while the Connect page shows only the kinds of device (watches, scales, rings) under each brand.

Where to find it#

The page is called “Connect Devices” (“Připojit zařízení” in Czech) and opens from “Devices” in the menu. Inside Settings, the “Devices” section shows the sources you already have under “Data sources”, with “Add a source” to go back to the full page. The Connect page groups the cards under “Your sources”, “Watches, rings and scales”, “Through our apps”, “Fitbit and Pixel Watch”, and a last group of brands we do not support yet. Within the brands the order is Garmin, Oura, Polar, Withings, COROS.

Each card has a badge. “Available” means you can connect it, “Connected” means data are flowing, and the others (“Waiting for data”, “Slow sync”, “No data flowing”, “Closed” and so on) are explained in Troubleshooting.

How to connect#

For Polar, Oura, Withings, COROS and Google Health the steps are the same:

1. On the Connect page, press “Connect” on the card. COROS has two buttons, “Connect (Europe)” and “Connect (rest of world)”: pick the region where your COROS account was created. If you are not sure, try Europe first, and use the other button if the sign-in does not work.
2. A window titled “Data processing consent” asks you to agree to the processing of your health data for your scores. Press “I agree & continue”.
3. You land on the maker's own sign-in page. You sign in there, so your password never reaches us, and you allow access.
4. You return to MyBodyAI. The card reads “Waiting for data”, and a line at the top says “Fetching your Polar data, this usually takes up to 30 minutes”, with the minutes counted. The charts stay empty until the data land.
5. When the first real data arrive, the line changes to “Your Polar data has arrived. Reload the page if you do not see it yet.” with a “Reload” button.

If the import takes longer than 30 minutes the line says “The Polar import is taking longer than usual” and adds that it keeps running on our side and you can close the app. We stop waiting after six hours. If a source has still delivered nothing after a day (12 hours for Polar, 3 days for Withings), its badge changes to “Nothing received”, and the advice in Troubleshooting applies.

Google Health starts with a short guide because a Fitbit or a Pixel Watch usually works better through Health Connect (see below). Garmin and the Android app have their own steps, in their sections below.

A few messages can appear when you return from the maker's page. “Connection was canceled” means you pressed Cancel there. “We could not confirm the link in time” means the card did not appear within a minute: try again. “The connection link has expired or was already used” means you should press “Connect” again. “This Garmin account is already linked to another MyBodyAI account” means each Garmin account can feed one MyBodyAI account only.

What each connection delivers#

The Connect page lists what we read from each source under “What we read” (press “Show what we read”). A small star marks a signal that only some models of the brand measure, and the line “What arrives exactly depends on the device model” applies to every card. The lists below follow those cards.

Garmin: the link, the export and the history#

The link. On the Garmin card press “Connect Garmin”, read the consent window, and sign in on Garmin's page. Garmin then marks MyBodyAI as “unverified”. This is Garmin's label for every app on its basic access level and says nothing about the app itself; you can remove the access at any time in Garmin Connect. After the link, new data arrive a few minutes after your watch next syncs with Garmin Connect. They include sleep and its stages, the sleep score, overnight HRV, resting and lowest heart rate, blood oxygen, breathing rate, stress, Body Battery, steps and the day's totals, and workouts recorded on Garmin's own devices.

What the link does not bring. Garmin sends data only from the moment you link, not the days before. Workouts that another app (ROUVY or Zwift, for example) uploads to Garmin Connect are not passed on by Garmin, so you add them yourself from a file.

The export. “Add history from an export” (the button reads “Import data” where the direct link is not offered to the account) opens a window that guides you through Garmin's data export: you ask Garmin for it on a computer, Garmin e-mails a link, and you upload the ZIP file back in the same window. It fills in up to 90 days before the link, once. It works only in a browser on a computer, not on a phone. Limits: 150 MB per upload, 250 files, and 90 days of history, with a choice of “Last 7 days”, “Last 14 days”, “Last month”, “Last 2 months” or “Last 90 days (max)”. A quicker per-day export (a ZIP named by date) works too, but it holds only the days you downloaded and no sleep length or stages. One workout can be added from its own FIT file, up to 5 MB. The export also carries VO2max and muscle mass from Garmin's files.

You do not need to repeat the export. Without the link you would have to upload a fresh one every few days, which is why the link is the better door. Once the link is open and the overnight HRV arrives on its own, the reminder to upload an export stays quiet.

How the three Garmin pieces fit. The link brings the new days. The export brings the older ones. On Android, our app also reads older steps, heart rate and sleep from Health Connect if the Garmin Connect app writes them there; Garmin writes no overnight HRV or stress to the phone, so only the export brings those for the older days. The Garmin watch app (below) can run next to all of this. Your HRV band needs about four weeks of nights, so an export makes it appear at once instead of after four weeks.

Health Connect through the Android app#

Health Connect is the Android health data store. It measures nothing itself: it collects what the other apps and watches on your phone write into it. The MyBodyAI app for Android reads it in the background. This is the way in for Samsung, Xiaomi, Pixel and many other watches, for a ring or a band whose own app writes to Health Connect, and for the steps the phone counts itself.

What we read: resting heart rate, HRV, SpO2, breathing rate, skin temperature, blood pressure, sleep and its phases, steps, active minutes, calories, activities, VO2max, weight and body fat. The Connect page marks many of these “select models only”, because Health Connect hands over only what the app writing into it publishes. Garmin Connect writes steps, heart rate and sleep. A bridge app can add HRV, SpO2 and breathing. A ring's app writes its own subset.

To connect, install the app from Google Play, open “Devices” and press “Connect Health Connect” on the card “Health Connect on this phone”. Android shows its own permission dialog. Pick background access as well, or the phone sends data only while the app is open and nothing overnight. A second permission, “Allow 90 days of history”, lets us read the 90 days before you connected. Without it Health Connect gives the app only the 30 days before the grant. The permissions themselves are granted and withdrawn on the phone, in the Health Connect app. If Health Connect is missing the card says so and points to the Play Store; on Android 13 and older it is a separate app that may need an update.

Samsung watches send sleep and heart rate to Health Connect through the Samsung Health app. Turn on its Health Connect link there, then allow Health Connect in MyBodyAI.

On an iPhone there is no Health Connect and Apple Health is not a source. A Fitbit can still be read through Google Health, and the other brands connect through their own accounts.

Polar#

Polar Flow data: sleep with stages, resting heart rate, overnight HRV, breathing rate, steps, active minutes, calories, workouts and weight. A chest strap such as the H10 delivers HRV but no sleep or steps, so a strap on its own fills only part of the picture. A Polar account with no watch or strap paired returns nothing, and its card says “Nothing received”.

Oura#

Sleep with stages, the sleep score and efficiency, overnight HRV, resting heart rate, blood oxygen, breathing rate, skin temperature, steps, active minutes, calories, workouts, VO2max and the ring's daytime stress. Skin temperature from a ring is a difference from your own baseline, not an absolute temperature. VO2max and vascular age from a ring are estimates, not measurements. For some services, disconnecting also deletes what came through the connection because the maker's terms require it; the confirmation window tells you when this applies.

Withings#

Weight, body fat, muscle and bone mass, hydration, visceral fat, vascular age and pulse wave velocity from a scale such as Body Cardio or Body Scan; blood pressure from a BPM monitor; sleep with stages, breathing disturbances and the apnea index from the Sleep Analyzer or ScanWatch; blood oxygen, resting heart rate, steps, workouts and, on a ScanWatch with electrodes, ECG; body temperature from the Thermo. Withings does not deliver HRV. A scale is allowed a longer silence than a watch before we call it quiet, because stepping on it every third week is normal use.

COROS#

Sleep with stages and the sleep score, overnight HRV, resting heart rate, steps, calories, workouts and the watch's daily stress average. COROS gives blood oxygen and breathing rate only from a manual check, so we do not read them. The two regional sign-ins exist because a COROS login only works in the region that holds the account.

Fitbit and Pixel Watch#

Google ended support for the Fitbit Web API on 30 September 2026 and set 30 October 2026 as the day it is switched off, so MyBodyAI opens no new Fitbit links and an old one stops syncing. There are two ways on. Which one fits you depends on your phone:

• Android: through Health Connect. In the Google Health app (formerly Fitbit) turn on sharing to Health Connect, sleep and heart rate included, and allow Health Connect in the MyBodyAI app. No Google sign-in is needed.
• iPhone, or when that does not work: through Google Health. Press “How to connect a Fitbit” on the Fitbit card, or use the Google Health card, and choose “Connect with a Google account”. Google then shows a warning that it has not verified MyBodyAI, and you can continue with the link on that screen. We read only what your Fitbit or Pixel devices recorded in the account: sleep, heart rate and HRV, blood oxygen, breathing rate, skin temperature during sleep, VO2max, steps, distance, active minutes, energy, workouts, weight and body fat. Copies that other apps put there are left out, so nothing counts twice. We write nothing into your account.

We do not read ECG through Google Health, and for some Fitbits Google Health returns no VO2max where the old interface did. A Pixel Watch needs an Android phone.

The Garmin watch app#

A small MyBodyAI app for Garmin watches, installed from the Connect IQ Store. It sends the day's stress, Body Battery and recovery time straight from the wrist, which Garmin writes into no phone. To pair it, open Settings, “Devices”, press “Generate pairing code” and enter the 6-character code in the Garmin Connect app under MyBodyAI, Settings, “Pairing Code”. Then open the app on the watch: the setting travels over Bluetooth, but the app picks it up only when it runs. The code is valid for 24 hours. If your watch model is not on the store page, a code will not help. One watch is paired to an account at a time, and pairing another replaces it. “Unpair watch” stops it at once, and the watch app then asks to be paired again.

How far back history reaches#

The three months are what the maker offers: a service that holds less gives less. If you disconnect a source that deletes its data and connect again, the last 90 days are read back. Garmin does not send past days again, so after a new Garmin link the data run from that day and an export covers the rest. See Sync for how new data keep arriving and Sources and overlap for what happens when two sources describe the same day.

How fast data arrive#

Most services tell us after your device has synced with its own app, and the data usually arrive within about 30 minutes. A safety pass every hour fetches anything missed. The Garmin link arrives a few minutes after the watch syncs with Garmin Connect. The phone reads Health Connect in the background about once an hour and whenever you open the app. The maker decides exactly when its data become available, and a watch that has not synced with its app has nothing to send. The full picture is on the Sync page.

What a tick and a dot mean#

Under “What we read”, each chip is a signal the app reads from that source. It does not promise that your model measures it. A colored dot inside a chip is the grade we give that kind of source for that signal (hover to read “gold tier”, “silver tier” or “bronze tier”), which the app words as top, good or basic quality. The same words appear on the small “measured · Oura” chip beside a number in the app. A star means “select models only”, for example ECG on Withings. “Compare what each brand measures” opens a table of all sources side by side.

Several devices at once#

You can connect any number of sources. The app keeps one value per signal per day and records which source wrote it. A second source mostly adds signals the first lacks, such as a scale next to a watch. Where two sources report the same thing, a fixed set of rules decides, and you can steer some of them. Sources and overlap explains them all.

Disconnecting#

Press “Disconnect” under the card, in the Connect page or in Settings, “Devices”. A window asks “Disconnect {name}?”. The data that already arrived stay in your account, and you can connect again at any time. When the maker's terms require it, the window says that disconnecting also deletes what came through that connection and what MyBodyAI computed from it, while data from your other devices stay. For the Garmin link the card offers its own disconnect and the export keeps its own: “Disconnect” keeps the Garmin data, “Disconnect and delete the Garmin data” removes what we know came from an export. The phone has a switch, “Use data from the phone”, in Settings, “Devices”: with it off, the app keeps sending but we discard it, and days already written stay. To stop Health Connect reading altogether, withdraw the permission in the Health Connect app. After a disconnect you see “{name} disconnected.” and the card returns to “Connect”.

Free and Premium#

Connecting a device is free. The free Premium week starts on the first day measured data reach your account and runs for 7 days. See Plans.

Frequently asked questions#

Which devices work with MyBodyAI?#

Garmin, Polar, Oura, Withings, COROS, Fitbit and Pixel Watch through Google Health, and any Android phone through Health Connect, which in turn carries Samsung, Xiaomi and many other watches. The list on the Connect page is the truth for your account.

Does MyBodyAI see my password?#

No. You sign in on the maker's own page, and we receive only the permission to read your data. You can remove that permission with the maker at any time.

I have an iPhone. What can I connect?#

Garmin, Polar, Oura, Withings and COROS connect through their accounts in a browser, and a Fitbit through Google Health. Apple Health and Apple Watch are not sources, and a Pixel Watch needs an Android phone.

Do I need the Android app if I connect Garmin?#

No. The Garmin link works on its own. The Android app adds older steps, heart rate and sleep from Health Connect for the days before the link, and it can run next to the link.

My Fitbit card says “Closed”. What now?#

The old Fitbit interface was switched off by Google. Press “How to connect a Fitbit” and choose one of the two ways above. Your history so far stays.

Can I connect two watches?#

Yes, but each signal on a given day comes from one of them. For steps you can pick the device you wear all day, see Sources and overlap.

Does disconnecting delete my data?#

Usually not: the data that already arrived stay. For a few services the maker's terms require deletion, and the confirmation window says so before you confirm. Deleting the account is a separate step, see Privacy and your data.