What a wearable integration actually includes
Most teams start by asking which API to call. The harder questions come later: how consent is captured and revoked, what happens when a user changes phones, how late-arriving data is reconciled, and how a heart rate sample from one device is distinguished from the same reading synced through a second app. A production integration answers these explicitly.
We treat a wearable integration as a small data platform with defined inputs, a canonical internal model, and documented outputs. That structure is what lets you add a second or third device source without rewriting the downstream logic each time.
Acquisition
On-device SDKs (HealthKit, Health Connect), vendor cloud APIs (Fitbit, Garmin, Oura, Withings, Polar) and direct Bluetooth connections to medical devices.
Authorization and consent
OAuth 2.0 flows, per-data-type permissions, token storage and refresh, and clean handling of revoked access.
Normalization
Consistent units, timestamps with timezone offsets, deduplication across sources, and device and app provenance on every record.
Delivery
APIs and events for your product, FHIR Observations for EHRs, and exports for analytics and research teams.
Choosing devices and platforms
Device choice drives most of the architecture. Apple HealthKit is on-device only: there is no Apple cloud API, so you need an iOS app that reads HealthKit and uploads to your backend. Google Health Connect is also on-device Android storage with per-data-type permissions, and apps that read health data must complete a health permissions declaration in Play Console. The older Google Fit APIs are deprecated and should not be the basis of new work.
Cloud APIs from vendors such as Fitbit and Garmin let your server pull or receive data without your own mobile app, but they come with their own approval steps. Fitbit's Web API uses OAuth 2.0, and server applications that need intraday data must request access from Fitbit. Garmin's Health API requires an approved business developer application before you can build against it. We help you plan around these lead times so they do not block a pilot.
For clinical programs that need regulated measurements, consumer wearables are often paired with FDA-cleared devices such as cellular blood pressure cuffs, scales and pulse oximeters. See remote patient monitoring integration for how those device types fit into an RPM program.
Data normalization and provenance
Raw wearable data is inconsistent in ways that matter clinically. One source reports weight in pounds, another in kilograms. One stores sleep as staged intervals, another as a nightly summary. Timestamps may be UTC, local time without an offset, or device time that drifted. The same step count can appear twice when a watch syncs to both a vendor app and HealthKit.
We map incoming data to a canonical model with UCUM units, explicit timezone offsets and source metadata recording which device, app and platform produced each value. Duplicate samples from overlapping sources are resolved with documented rules rather than silently summed. When data goes to an EHR, each measurement type is mapped to an appropriate LOINC code so it lands as a structured FHIR Observation rather than a free-text note.
- Unit conversion to UCUM with original values retained
- Timezone-aware timestamps and handling of device clock drift
- Source priority and deduplication rules per data type
- Device model, firmware and app version recorded where available
- LOINC mapping for EHR-bound observations
Getting data into clinical systems
Clinicians rarely want every sample. A cardiology team may want resting heart rate trends and flagged irregular rhythm events; an RPM nurse wants today's blood pressure readings and who has not transmitted. We design the summarization and alerting layer with your clinical stakeholders so the EHR receives what is useful rather than a firehose.
Our EHR wearable integration work covers FHIR R4 APIs where the EHR supports writing Observations, HL7 v2 interfaces where it does not, and SMART on FHIR apps for in-context review. The approach depends on your EHR, your interface team's capacity and the workflows you want to support.
Security and HIPAA-aligned controls
Wearable data tied to a patient is protected health information once it enters a covered entity's workflow. We design pipelines with HIPAA-aligned controls: encryption in transit and at rest, scoped service credentials, audit logging of access and changes, data minimization, and retention rules you can configure.
Technical controls are only part of compliance. Whether a deployment meets HIPAA requirements depends on your overall compliance program, your policies, your risk analysis and the business associate agreements in place with each vendor that handles the data. We document the data flows and controls so your privacy and security teams can assess them. More detail is on our HIPAA-aligned wearable integration page.
How an engagement is structured
Work usually starts with a short discovery phase to confirm devices, data types, destinations and regulatory context. From there we produce an integration design, build a working pipeline for one device source end to end, and then extend to additional sources and destinations.
We can build the integration for your team to own, extend an existing platform, or review an architecture you have already started. Before a first call, the integration requirements checklist helps you gather the details that shape scope.
- Discovery: devices, data types, users, destinations, constraints
- Design: data model, auth, sync strategy, security controls
- Build: first source end to end, then additional sources
- Handover: documentation, runbooks and monitoring
Frequently asked questions
Which wearable platforms can you integrate with?
We work with on-device platforms such as Apple HealthKit and Google Health Connect, vendor cloud APIs such as Fitbit, Garmin, Oura, Withings and Polar, Samsung Health, continuous glucose monitors, and Bluetooth medical devices. The right mix depends on your patient population, the data types you need and whether you need FDA-cleared measurements.
Do we need our own mobile app?
If you need Apple HealthKit data, yes, because HealthKit has no cloud API and data must be read on the iPhone by an app the user installs. The same applies to Google Health Connect on Android. Vendor cloud APIs such as Fitbit or Garmin can be integrated server to server without your own app, after the user authorizes access.
How long does vendor approval take?
It varies by vendor and is outside our control. Garmin requires an approved business developer application, Fitbit intraday access for server apps requires a request to Fitbit, and Google Play reviews health permissions declarations. We plan these steps early so approvals run in parallel with build work.
Can wearable data be written into our EHR?
Often, yes. Many EHRs accept FHIR Observations or HL7 v2 results, and some support SMART on FHIR apps for reviewing device data in context. What is possible depends on your EHR vendor, your organization's interface policies and which data clinicians actually want in the chart.
Is the integration HIPAA compliant?
We build with HIPAA-aligned controls such as encryption, access controls and audit logging, and we document data flows for your review. Compliance itself depends on your overall program, policies, risk analysis and the BAAs you hold with each vendor in the data path, so it is a determination your organization makes.