Lean bulk and cut. By trend, not by feel.

For natural lifters and anyone who wants to run a lean bulk or a cut properly. Lean is law is a trend and body app: weight, phases, calories and macros, supplements and weekly check-ins with posing photos. There is no workout log.

Yes. On iPhone, Lean is law works with Apple Health, on Android with Health Connect for weight, body fat and nutrition. iCloud backup and widgets are iPhone only. You buy Pro in your device's store.

Your weight fluctuates by up to 1 to 2 kg from day to day, due to water, salt, carbs and glycogen. The trend weight smooths out these fluctuations and shows where things are really heading. The default is exponential smoothing: each new weigh-in pulls the trend only a little towards it, older values fade out slowly. Under "Settings & more → Trend method" you can choose the 7 or 14 day moving average or double exponential smoothing instead.

In a lean bulk you might gain 0.3 kg a week, while water, salt, carbs and glycogen move the scale by 1 to 2 kg from one day to the next. A refeed or a hard leg day easily adds a kilo overnight. Going by the daily value, you would cut calories after every spike and add them after every dip. The trend smooths this noise and shows after one or two weeks whether your pace is right.

A phase is a period with a clear direction: bulk to build muscle, cut to lose fat, maintain to keep your weight stable and diet break as a planned pause of usually two weeks within a long cut. Lean is law measures the pace in percent of your trend weight per week. Common ranges are 0.25 to 0.5% for a lean bulk (default 0.35%) and 0.5 to 1.0% for a cut (default 0.7%). Lean is law warns you above 0.5% in a bulk and above 1.0% in a cut. A new phase ends the previous one, and you can plan the next one in advance. These are guide values, not medical advice.

Lean is law takes your average intake over the last 14 days and accounts for what your trend did in that time. One kilogram of body weight counts as about 7,700 kcal. Example: you ate 2,800 kcal a day and your trend rose by 0.2 kg a week, so your TDEE is about 2,580 kcal. Only days with entries count, and it needs at least 7 logged days. Until then Lean is law estimates your needs from height, age, sex and activity (Mifflin-St Jeor) and marks the value as estimated. Adaptive TDEE, target calories and macro targets are part of Lean is law Pro.

Both work. Use the plus button and "Food" to log a meal: calories, and optionally protein, carbs and fat. Or Lean is law reads your nutrition from Apple Health or Health Connect, where many nutrition apps write their entries. Your daily value is your own entries plus those of other apps; Lean is law skips its own entries in Health so nothing counts twice. Logging calories is free.

Under "Settings & more → Supplements" you add what you take, for example creatine 5 g, with times and weekdays. Lean is law reminds you with a notification, and you tap "Taken" right there or tick it off on the "Supplements" card. Lean is law gives no advice on supplements or doses. Supplement reminders are free.

Once a week, on your check-in day (Sunday by default), you take four poses: front, back, side and lat spread. The "Weekly check-in" card shows how many poses are done, your weekly average, your rate, your waist and a note. Check-ins are free. Comparing the same pose on two dates side by side and sharing a check-in as an image are part of Lean is law Pro.

A straight line is fitted through the trend values of the last 14 days. Its slope is your weekly rate. From this, Lean is law works out when you will reach your phase's goal weight or the next milestone if things continue as in the last two weeks, and compares that with your planned pace. The forecast is part of Lean is law Pro.

In the maintain phase or a diet break there is a corridor around your weight, ±1.5% by default. You set the width yourself, in percent or as a fixed amount. The band in the chart and the status are free. With Pro you see how long your trend has been inside the corridor and get an early warning when it leaves or would soon leave it.

Free: logging weight, trend, 7-day change, history, Apple Health or Health Connect, phases with pace warning and phase history, logging calories and macros, supplement reminders, the weekly check-in with posing photos, experiments and markers, the maintain corridor with band and status, one reminder, export and sharing as an image. Lean is law Pro unlocks adaptive TDEE, target calories and macro targets, the forecast to the end of your phase, long chart ranges, pose comparison, sharing a check-in as an image, the milestone card, patterns, balance, monthly reports, body measurements, experiment evaluation, trend restart, corridor history and early warning, and on iPhone the iCloud backup and the larger widgets. Pro is available as a monthly or yearly subscription and as a one-time purchase without a subscription.

Yes. By default all data stays on your device; Lean is law has no server and no account. Your onboarding answers stay on the device too. On iPhone you can optionally turn on an automatic backup to your own iCloud account under "Export, backup & import", for switching devices. We have no access to it. On Android you take your data with you as a JSON backup.

You take photos with the camera or pick them from your library. Lean is law resizes them and stores them only on your device, with date, pose and trend weight. They are part of the file export (JSON), not of the iCloud backup. Lean is law never uploads them.

Under "Settings & more → Manage subscription & purchases" you can see your subscription, change or cancel it and restore earlier purchases. Billing runs through the App Store or Google Play. If you bought Pro as a one-time purchase, it stays active for good.