High-Jump: Offline-First Native Workout & Fitness Engine
A high-performance workout tracker engineered for Android (Kotlin, Jetpack Compose, Material 3) and iOS/Web with a shared Supabase backend. Built offline-first with local Room database seeding, routine builders, and real-time biometric telemetry.
Client
High-Jump
Headline metric
876
Tech stack
Kotlin · Jetpack Compose · Material 3 · Hilt · Room DB · Supabase · Ktor
The situation
Most fitness apps fail inside gym basements with poor cellular reception, trapping users in loading spinners when they need to log their sets, weights, and rest timers in real-time.
What we did
- Engineered an offline-first architecture using Room DB pre-seeded with 876 public-domain exercises for instant zero-latency logging.
- Built a sleek, modern UI with Jetpack Compose and Material 3, supporting swappable accent palettes and dynamic dark mode.
- Integrated Supabase cloud synchronization via Ktor + supabase-kt to seamlessly sync workouts, routines, and social sharing when connectivity resumes.
- Designed analytics routines and progress visualization tracking 1-rep max curves, volume per muscle group, and rest intervals.
What we shipped.
0ms
Logging latency with fully offline Room database
876
Exercises bundled directly into local APK asset
100%
Sync fidelity with Supabase Postgres backend
How it shipped.
Scaffolding & Offline DB
Phase 1
Room schema, exercise database seeding, and Jetpack Compose theme setup
Workout Logging & Routines
Phase 2
Set-by-set tracker, rest timers, and custom routine builder
Cloud Sync & Analytics
Phase 3
Supabase authentication, background Ktor synchronization, and progress charts
“The app runs fully offline out of the box with zero lag in the gym, syncing seamlessly with Supabase once back on Wi-Fi.”
Mobile Architecture Team
High-Jump
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