Best iOS weight tracker apps in 2026
Weight trackers all show numbers and dots. The differences that matter: how they handle the day-to-day noise (a bad weigh-in shouldn't ruin your week), HealthKit integration, and whether your data leaves the device. We ship one (BodiLog) and have evaluated most of the others. Here's an honest comparison.
What separates a good tracker from a bad one
- Trend over reading. A 7-day moving average matters more than today's number.
- HealthKit two-way sync. The tracker should write to and read from Apple Health, not its own silo.
- No third-party trackers. Weight is sensitive data. The privacy nutrition label should fit on one screen.
- Reasonable subscription model. Weight tracking should not cost $9.99/week.
1. Happy Scale
Best for: users who want serious trend math. Happy Scale was the original 'smooth the line' weight tracker. Forecast features, plateau warnings, weekly trend deltas.
Trade-off: aging UI; Apple Watch is acceptable. One-time + optional unlock.
2. BodiLog (mk0.net)
Best for: users who want a clean SwiftUI tracker with strong HealthKit integration. BodiLog writes every entry to HealthKit, draws a smoothed trend line, supports BMI and goal tracking, and ships a focused widget.
Trade-off: shipped in 2025, smaller community than Happy Scale. No Apple Watch app yet. We documented the architecture separately.
3. Libra (Android - for context)
Mentioning because this is consistently asked: Libra is the Android-native weight tracker that inspired Happy Scale. There's no iOS port. If you want Libra on iOS, Happy Scale is the closest spiritual successor.
4. Apple Health (built-in)
Best for: users who only weigh occasionally and don't need trend smoothing. Apple Health logs body mass natively, integrates with smart scales over Bluetooth, and shows simple charts.
Trade-off: the Health app's chart for body mass is functional but not insightful. No trend forecast. No widget for quick logging.
5. MyNetDiary / MyFitnessPal
Best for: users who want weight tracking inside a calorie tracker. Both have weight as a sub-feature.
Trade-off: the calorie tracker context turns weight into a side feature. Privacy posture is not great - both ship with significant third-party SDKs.
Our pick by use case
- Trend math obsessive: Happy Scale
- Clean SwiftUI + HealthKit-first + privacy: BodiLog
- I just need a number: Apple Health
- Weight + calorie tracking: MyNetDiary (cleaner privacy than MyFitnessPal in 2026)
Honest disclosure
We make BodiLog. We've ranked it second to Happy Scale for users who specifically want forecast features, because Happy Scale's math is genuinely better at that one thing. For most people, our trend smoothing + clean HealthKit story is enough.