Apps don't lose weight for you. But the right ones make compliance easier, and compliance is ~90 % of the game. Ten apps with a real behavioural loop behind them, each addressing a specific part of the weight-loss puzzle.

1. MacroFactor

Calorie tracking with adaptive TDEE estimation. Unlike older trackers, it calibrates to your actual rate of change, not generic formulas. Best-in-class in 2026.

2. MyFitnessPal

Older, bigger food database. Free tier works; paid ads get annoying. A default choice if you want the broadest food catalogue.

3. Cronometer

Strongest on micronutrient tracking. For people who also care about getting the nutrition right, not just the calories.

4. Strong / Hevy

Simple strength-training loggers. Track sets, reps, weight, and progressive overload. Critical for preserving muscle during a deficit.

5. Apple Health / Google Fit

Step tracking + sleep + heart rate in one. Aggregates data from wearables; good baseline overview.

6. Streaks / Way of Life

Habit trackers. Useful for turning daily walks, protein targets, and sleep bedtimes into visible streaks that hold through low- motivation days.

7. Zero / LIFE Fasting Tracker

If intermittent fasting is your chosen structure. Tracks fasting windows, graphs patterns. Optional, not required.

8. MyPlate

Simpler than MyFitnessPal. Good for beginners who find full macro tracking overwhelming.

9. Headspace / Calm

Surprising inclusion — sleep and stress are weight-loss variables. Meditation apps with sleep content support those.

10. Sleep Cycle / AutoSleep

Sleep tracking makes sleep habits visible. Visible habits change; invisible ones don't.

A realistic stack

One tracker (MacroFactor or MyFitnessPal), one lifting logger (Strong), one habit tracker (Streaks), Apple Health or Google Fit for steps. Four apps. They won't replace diet discipline — they make diet discipline measurable, which is the actual lever.