Every question the Migrations pages answer

The 11 migrations pages answer 53 named questions between them. Every one is listed below, and every link lands on the paragraph that answers it rather than the top of the page.

How to migrate from Google Fit to Health Connect

Can I just re-point my backend from the Fit REST API to Health Connect?No. Health Connect is an on-device store with no server endpoint, so there is no URL for your backend to call. If you read Fit…
When are the Google Fit APIs actually shutting down?Google's Fit migration guide (updated September 10, 2026) says the Google Fit API, including the REST API, will only be supported until the…
Will my users' Google Fit history transfer to Health Connect?Not fully. Health Connect only holds data that is on that device or written by connected apps; it is not a backfill of a user's entire…
Do users have to reconnect, or does Fit consent carry over?Users must reconnect. There is no silent migration of Google Fit consent to Health Connect; Health Connect uses an OS-level permission…
What replaces Google Fit for my iOS users?Not Health Connect, which is Android-only. If your iOS app read a user's Google Fit data through the REST API, that path loses support…

Migrating from the Fitbit Web API to the Google Health API

Will my existing Fitbit access and refresh tokens work with the Google Health API?No. Google's Health API migration guide says existing access and refresh tokens cannot be transferred, so with the move to Google OAuth 2.0…
When exactly is the legacy Fitbit Web API being shut down?On October 30, 2026. Google's Google Health API page (read October 12, 2026) lists September 30, 2026 as the end of support, when the API…
Do users need a Google Account to keep their Fitbit connection?Yes, for the Google Health API. Google's Health API migration guide says a user must sign in to the Google Health mobile app to link Google…
Can an aggregator handle this migration for me?Potentially. A health-data aggregator that already supports both the legacy Fitbit Web API and the new Google Health API can absorb the…
Is the Google Health API the same as Health Connect?No. The Google Health API is a cloud REST API (the Fitbit Web API successor) that your backend calls over Google OAuth 2.0. Health Connect…

Adding Android to a HealthKit app

Is there an official cross-platform SDK for HealthKit and Health Connect?No. There is no first-party Apple or Google product that speaks both. You either build two native integrations with your own normalization…
Can I read HealthKit or Health Connect data from my server?No. Both are on-device stores with no server endpoint. You read the data inside the app on the device and sync it to your own backend…
Do HealthKit data types map one-to-one to Health Connect?Core types like steps, distance, heart rate, calories, sleep sessions, weight, and workouts map reasonably, but names, units, granularity,…
Why does HealthKit return empty data instead of a permission error?By design, HealthKit does not tell you a read was denied; it returns empty data instead, so you cannot infer a user's health status from…
Should I go native on both platforms or use an aggregator?Per-platform native gives the most control and no recurring cost, but you build and maintain two integrations, two permission flows, two…

Consolidate wearables: replace direct integrations with one aggregator

Do users have to reconnect when I move to an aggregator?Yes. OAuth grants and refresh tokens are bound to your old per-vendor apps and do not transfer. Every user must re-authorize through the…
If I use one aggregator, do I still need my own developer credentials?Often yes. 'One integration' is shorthand: providers such as Garmin, WHOOP, and Fitbit may still require you to register and get approved…
Will the normalized schema drop provider-specific fields?It can. A unified schema flattens or drops fields that only exist on one provider. If you depend on a raw provider field, confirm the…
How far back can I back-fill historical data?Back-fill depth is set by each underlying provider, not the aggregator, and it is capped and often permission-gated. Large ranges are…
Should I hard-cut or run both in parallel?Run both in parallel. Stand up the aggregator alongside your existing integrations, dual-read and compare for a validation window, migrate…

Migrate from an aggregator to direct provider integrations

Do user connections transfer from the aggregator to my direct integration?No. OAuth grants and refresh tokens are bound to the aggregator's app and do not transfer to your own app. Every user must re-authorize…
Which providers require their own approval when I go direct?Several gate access behind review even when you integrate directly. As of 2026, Garmin's Health API runs through a partner-program…
Will I get the raw provider fields the aggregator's normalized schema dropped?Often yes - direct access to a provider's raw schema is a common reason to leave. But confirm the provider still exposes that specific…
How far back can I back-fill history after going direct?Back-fill depth is capped by each provider, not by you or the aggregator, and large ranges are often delivered asynchronously. Verify…
Is going direct actually cheaper?It can be for high-volume providers where per-connection or per-MAU aggregator fees exceed in-house cost, but it is not pure savings. You…

How to switch from one health data aggregator to another

Do my users have to reconnect when I switch aggregators?Yes, in almost all cases. OAuth grants and refresh tokens are bound to the old aggregator's app and do not transfer to the new one, so each…
Can I just re-point my webhook to the new aggregator?No. Aggregators use different webhook signatures and event models (for example Terra's terra-signature HMAC versus another vendor's…
Will switching aggregators let me back-fill more history?No. Back-fill depth is set by each underlying provider, not by the aggregator you use. Terra documents different per-provider caps, and…
Is coverage the same across aggregators?Not necessarily. Coverage differs by aggregator and shifts over time, and parity is per-provider and per-field. Confirm the new aggregator…
How long should I run both aggregators in parallel?Long enough to migrate users in waves, validate data continuity per cohort, and confirm reconnection rates. Keep the old path live and a…

Migrate from polling to webhooks for a fitness API

Does the webhook payload contain the full activity data?Often not. Many providers send a notification with an object id (Strava webhook events carry object and aspect ids, not the full activity)…
Can I stop polling once webhooks are live?Not entirely. Webhooks are best-effort and can be missed during endpoint downtime or dropped deliveries, with no built-in catch-up. Keep a…
Why do I need idempotency and ordering guards?Webhook delivery is at-least-once and not ordered, so the same event can arrive more than once and out of sequence. Dedupe on a unique…
How many webhook subscriptions can I create?It depends on the provider. Some cap subscriptions per app - Strava is documented as one push subscription per application. Do not hardcode…
Will webhooks lower my rate-limit usage?Generally yes, because you stop spending request budget polling for unchanged data and only act when an event fires. Actual limits vary and…

Adapting Your Integration to Strava's API Changes Since 2024

What changed in Strava's API since 2024?At a high level, and rolling out over time: formal developer tiers (Standard and Extended Access), a Developer Program review with display…
Can I still use an aggregator for Strava data?Possibly not. Strava's API Policy, effective June 1, 2026, prohibits operating, offering or facilitating any intermediary or aggregator…
Do I have to reformat or remove data I already store?Possibly. How athlete data can be displayed and retained is constrained by the current terms, so a field you store or render today may need…
Will my athletes have to reconnect?Athlete permission and consent are required and must be visible in your UI. If you change how you collect consent to meet current…
What are the current rate limits and tier caps?Strava documents default limits (overall vs non-upload, per-window and per-day) and a limited athlete cap on the Standard tier, but the…

Keep Users Connected During a Fitness API Migration

Do OAuth tokens transfer to the new integration?Almost never. Refresh tokens and provider grants are bound to your old app or aggregator, so the new path needs a fresh user authorization.…
Can I back-fill a user's full history on the new source?Usually only partially. How far back you can restore is capped by each underlying provider, not by you or your integration partner, and…
How do I avoid losing users who never reconnect?Track per-user connection state (old-connected, reconnected, failed) so reminders target only those who still need to act, and keep the old…
Should I cut everyone over at once?No. Migrate in waves with monitoring on both paths, and hold a rollback option until each cohort is validated. A big-bang cutover with no…

Migrate off a deprecated fitness API

Can I keep my users' existing connections and tokens?Generally no. Because the successor changes the OAuth provider/library or moves from OAuth scopes to OS-level permissions, access and…
Will I get all my historical data on the new API?Usually not fully. Back-fill depth is set by each underlying provider, not by you, and on-device successors often gate history behind a…
Do I have to re-architect if the successor is on-device?If you previously read data server-to-server and the successor is an on-device store (Health Connect or HealthKit), yes. On-device stores…
Can an aggregator remove the need to migrate at all?It can shift the burden. An aggregator that already supports both the old and successor APIs can absorb the cutover so you keep one…

Fitbit Data for Research Studies After the Web API Turndown

What happens to a study participant's Fitbit data if they have not re-authorized by October 30, 2026?Google says the data stays available as long as the participant keeps syncing their device to the Google Health app, but your dataset may…
What goes into Google's Health Research Attestation for a Fitbit study?Google's research policy lists four items: a completed intake form, the IRB or ethics committee approval or waiver letter, the board's…
Should a study team build its own Google Health API integration or use a research data platform?Our recommendation is to build only if you already have engineers who can run Google OAuth, webhooks and the Restricted-scope review within…
Can a pediatric study keep collecting from Fitbit Ace devices through the Google Health API?No. Google's data-types page notes that Fitbit Ace devices are not supported by the Health API, and Google says the Fitbit Web API stops…
Do participants who already signed our consent form have to consent again for the Google Health API?They at least have to re-authorize, because Google says existing Fitbit access and refresh tokens cannot be transferred, which requires…

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