Health, home and travel decision
Fitbod
The core loop is buildable, but a dependable replacement becomes a real weekend or multi-day project. For Fitbod, build moderate workout plans from user-selected equipment and recovery notes. The hard boundary is exercise library, adaptive programming, mobile capture, wearables, and coaching models, plus hardware data, content, coaching, and trust.
Visit website↗Open-source builds that already do this
Every project below is open source and already does this job today. Fork one, self-host it, or take the parts you need — the build prompt further down assumes an empty file, and this is the shortcut past that. Licences differ; check the one on each card before you ship.
What a replacement has to do
- Log workouts and recovery notes, plan moderate routines from user-selected equipment, and show trends without diagnosing, shaming, or enforcing restrictive goals.
What it still won’t have
- exercise library, adaptive programming, mobile capture, wearables, and coaching models
- wearable hardware data
- coach network
- clinical validation
- large content library and social network
What remains hard
- Physical hardware
- Content rights
- Execution quality
First-year cost
The build hours below are a category default, not an estimate for this product. Change them to your own numbers and the comparison follows.
Keep paying
Paying is—cheaper in year one.
On cash alone, building overtakes the subscription at 1 seat.
Money you would actually spend
Time you would spend
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What you would spend
What we assumed
The verdict above measures whether you could build it. This one is only about money.
Runnable build prompt
Build a personal replacement for Fitbod in an empty repository. Use React Native with Expo, TypeScript, SQLite, and HealthKit or Health Connect only when explicitly enabled; do not offer alternative stacks. The core loop is: log workouts and recovery notes, plan moderate routines from user-selected equipment, and show trends without diagnosing, shaming, or enforcing restrictive goals. Make the first run work locally with one documented command. Store all user data locally by default and make export straightforward. Put secrets in .env, ship .env.example, and never commit credentials. Create optional logs for activity, sleep, mood, energy, and personal notes with editable units. Let the user build moderate routines and rest days without weight-loss targets, punishment, or competitive pressure. Request health-platform permissions per data type and work fully without granting them. Show weekly patterns and consistency with neutral language and no diagnostic or body-image judgments. Add reminders that can be muted, data export, account-free local use, and full deletion. Include a clear statement that the app is not medical care and should not replace qualified advice. Include clear empty, loading, success, and recoverable error states. Add input validation, safe filenames, and graceful handling of unavailable APIs. Write focused tests for the core transformation and one end-to-end happy path. Create a README with setup, architecture, permissions, data location, and backup steps. Do not add accounts, billing, telemetry, analytics, or a hosted control plane. Deliberately leave out medical diagnosis or treatment. Deliberately leave out extreme exercise or restrictive-eating coaching. Deliberately leave out wearable hardware, human coaching, and a large social network. Finish by running the tests and listing the exact commands used.
