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Use case

Wearable API for Fitness Apps

Pull workouts, heart rate, recovery and sleep from the devices your members already wear.

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Fitness & coaching apps

A coaching app lives or dies on whether it can see what the athlete actually did. Members own a mix of Garmin watches, WHOOP bands, Oura rings and Apple Watches, and the first support ticket after launch is always "why does it not sync with my device?"

WearLink gives a fitness product one integration for the cloud providers and one mobile SDK for the on-device stores. Workouts arrive in SI units with the same object shape from every source, and recovery inputs — HRV, resting heart rate, sleep — land beside them so a readiness view can be built once.

The parts that usually eat a sprint — Strava webhook subscriptions, Fitbit intraday approval, Oura documents being revised after the fact — are handled below the API surface and documented on the individual integration pages.

What usually goes wrong

Every device has a different workout schema

Garmin reports power in watts and pace in seconds per kilometre; Strava reports speed in metres per second; Fitbit reports neither. Charting them together without normalisation produces a comparison that looks meaningful and is not.

Recovery needs three metrics from two devices

A readiness score wants overnight HRV, resting heart rate and sleep duration. Users often have those on a ring and their workouts on a watch. Your product has to join across providers on the same user.

Polling burns your vendor rate limits

Fitbit and Oura enforce per-application quotas. Polling every user every few minutes exhausts them before you reach a few hundred members. Webhooks are the only pattern that scales, and each vendor implements them differently.

How WearLink handles it

  • Workouts normalised to SI — Distance in metres, duration in seconds, power in watts, speed in metres per second, with per-provider originals preserved for audit.
  • One user, many devices — A single end-user record can hold Oura for sleep and Garmin for workouts. Summaries and webhooks are keyed by your user, not by the provider.
  • Webhooks instead of polling — Subscribe to workout.created, sleep.created and recovery_score.created. WearLink holds the vendor subscriptions and re-delivers when a record is revised.
  • Energy balance for nutrition-aware coaching — Pair wearable burn with photo or manual meal logs for a daily calories-in versus calories-out view on paid plans.

FAQ

Fitness & coaching apps — frequently asked

Can I get Strava activities in real time?
Yes. WearLink holds a registered Strava webhook subscription, so a new activity produces a workout.created event to your endpoint shortly after the athlete uploads it.
Does WearLink support Apple Watch workouts?
Apple Watch data lives in Apple Health, which has no cloud API. The Swift package reads HealthKit on the phone and pushes into the same pipeline, so workouts arrive in the same schema as Garmin or Strava.
Do I need my own Oura or WHOOP developer application?
No. Your users authorise against WearLink’s registered applications through the hosted connect flow. You can supply your own credentials later if you want the consent screen to carry your brand.
What does it cost for a coaching app with a few hundred members?
The Developer tier covers 50 end-users and Scale covers 1,000, both flat monthly prices. There are no per-user credits, so an athlete who trains twice a day does not cost more than one who trains twice a week.

Other use cases

Same API, different products

Clinical & remote monitoring

Heart rate, blood pressure, glucose and sleep from consumer devices, in one auditable pipeline.

Corporate wellness

Steps, sleep and activity challenges across every device an employee brings, with per-user consent.

Insurance & incentive programmes

Verified activity and sleep data for behaviour-based incentives, with an audit trail behind every reward.

Research & digital biomarkers

High-resolution series from consumer wearables, with units and provenance you can cite.

Connect your first wearable today

Free for up to 3 connected users. No credit card. Your first API key is issued the moment you sign up.

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