Mobile and companion apps for Apple Watch, wearables, and IoT devices — turning continuous hardware data into experiences users actually act on.
Tools & Technologies
Full-cycle IoT health app connecting wearable hardware to a real-time data pipeline and an AI wellness engine — all surfaced through a companion app that makes continuous biometric data feel like a personal health coach rather than a spreadsheet. Built from concept to App Store in under 14 weeks.
"The result is an app our users describe as the first health tool that genuinely understands them."— Sarah Rehman, Founder @ Vitamind
Behaviour-tracking app that reads motion, activity, and usage patterns from wearable sensors to build a real-time model of each user's daily routine — then predicts slip moments before they happen and delivers a nudge via Apple Watch complication or Wear OS tile at exactly the right time. The intervention happens on the wrist, not buried in a notification stack.
"HabitForge doesn't just track what I do — it predicts what I'm about to do and gently course-corrects me right from my wrist."— Alex Chen, Early Adopter
We integrate with Apple Watch, Garmin, Fitbit, Oura, Withings, and custom BLE hardware — as long as the device exposes a documented SDK, BLE profile, or MQTT interface, we can connect to it. We assess hardware compatibility in discovery so you know what's possible before build starts, not halfway through it.
Wearables transmit around the clock. The data pipeline — ingestion, processing, storage, and push delivery — has to be reliable at 3am when no one is watching, not just during a demo. We architect for continuous load from the first sprint and test with realistic device transmission frequencies before launch.
Biometric and health data is regulated differently to standard app data in most jurisdictions — HealthKit usage rules, HIPAA considerations for US health apps, and GDPR health data provisions for EU products. We flag the relevant requirements at the start of every health IoT engagement and build to them from the first data model, not as a compliance pass before submission.
Raw sensor output — heart rate variability, glucose trends, sleep stages, motion patterns — translated into plain-language insights at the right moment. Not a dashboard of numbers users screenshot once and never check again. Actionable recommendations surfaced when the data is fresh and the moment is right.
watchOS and Wear OS apps built for the glanceable constraints of a wrist screen — complications that show what matters at a glance, quick-action tiles that don't require the phone, and notification logic that respects Do Not Disturb rather than firing on every data point. The watch app earns its place on the wrist or users remove it.
Wearable devices don't pause. The backend infrastructure — ingestion, processing, and push delivery — is load-tested against realistic continuous transmission rates before launch. You find out about capacity limits in staging, not when a thousand users sync simultaneously after a firmware update.
Apple's HealthKit has strict usage requirements — what you can store, what you can share, and what you must declare. We read the policy before writing the schema, not after the first App Store rejection. If your product touches HIPAA or GDPR health data provisions, we'll identify the requirements in discovery and build to them throughout.
App Stop takes ownership of both product thinking and execution. We combine design clarity, engineering discipline, and market context to ship experiences that are fast, usable, and ready to scale.
Delivery Model
We define the product problem, success metrics, and the delivery track that fits the business.
We shape the technical foundation, delivery milestones, and risk controls before sprint work begins.
We execute in focused iterations with demos, QA, instrumentation, and release planning in parallel.
We launch with observability, support, and a practical roadmap for what comes next.
Selected Work
FAQ
We focus on the software side — the mobile app, companion experience, and cloud data pipeline. If you have existing hardware or a hardware partner, we integrate with their SDK, BLE profile, or MQTT interface. If you're still evaluating hardware options, we can advise on which devices have the most mature development ecosystems for your specific use case and user base before you commit to a manufacturer.
Yes — this is the most common setup. We've integrated with Apple Watch, Garmin, Fitbit, Oura, Withings, and custom BLE hardware. As long as the device exposes a documented SDK, BLE GATT profile, or API, we can connect to it. We assess hardware compatibility during discovery and flag any firmware or API limitations that affect the feature set before build starts — so you're not discovering constraints six weeks into the sprint.
We treat biometric and health data as sensitive by default regardless of whether your product is formally regulated. Data minimisation, on-device processing where possible, encrypted transit and storage, and granular user consent flows are standard in every health app we build. If your product falls under HIPAA — typically if you're working with US healthcare providers or payers — we'll identify the specific technical safeguard requirements early and build to them from the first data model. Same applies to GDPR special category data provisions for EU products. We're not lawyers and won't give legal advice, but we know what the technical requirements look like and we build to them.
We design for disconnection as a normal state, not an edge case. Wearables go out of Bluetooth range constantly — during a workout, overnight, when the phone is left in another room. We build local storage on the device side so data is buffered and synced when the connection resumes, offline-capable UI states so the app is still useful without a live connection, and sync reconciliation logic that handles gaps in transmission without corrupting the user's historical data. Connectivity failure shouldn't mean data loss or a broken experience.
Yes, and it's one of the more common requests. Apple Watch (watchOS) and Android wearables (Wear OS) are separate development targets with different APIs, different design conventions, and different capability sets — but a shared mobile app core means most of the business logic, data pipeline, and sync architecture is written once. We'll scope them as parallel workstreams with a shared backend rather than two completely separate projects, which keeps cost and timeline proportionate to the actual incremental work involved.
