Semly icon

Your GLP-1 treatment,
under control.

Semly tracks your weight, your medication and your progress — all stored on your iPhone or iPad, with no accounts, no ads, and your health data never leaving your device.

Available for iPhone and iPad.

Semly's Home screen, showing current weight, deltas and an evolution chart
Daily log

Every day, one step closer to your goal

Log your weight, mood, symptoms and measurements in seconds. Semly organizes your full history by month, with search and filters.

  • Weight, measurements and body composition
  • Mood, hunger and energy in one tap
  • Private progress photos, never in the cloud unless you choose to
  • Fully customizable day tags
Semly's Log screen, with a list of weight entries by date
Treatment

Never lose track of your medication

Compatible with Ozempic, Wegovy, Mounjaro, Zepbound, Saxenda or any other GLP-1 treatment. Semly automatically rotates your injection site and warns you when a pen is running low.

  • Automatic, smart injection-site rotation
  • Pen inventory with doses remaining
  • Injection reminders and prescription renewal alerts
  • Side-effect tracking per specific dose
Ozempic Wegovy Mounjaro Zepbound Saxenda Other
Semly's Treatment screen, with the active plan and next injection
Progress

See where you're heading, not just where you are

8 interactive charts, advanced statistics and predictions at 30, 60, 90, 180 and 365 days with a confidence interval — so you know, with real data, when you'll reach your goal.

  • Moving average, trend line and BMI
  • Estimated date to reach your goal
  • Weekly weight-loss pace
  • Share your progress as an image
Semly's Progress screen, with a downward weight chart and predictions
Motivation

Every kilo, every week, every dose counts

11 unlockable achievements, a motivational message that changes every day, and a visual celebration every time you hit a milestone — so sticking to your treatment feels like progress, not a chore.

  • 11 unlockable badges
  • Streaks and milestones every 5 kg
  • A different motivational message every day
  • Monthly calendar with your progress at a glance
Semly's Achievements screen, with unlocked and locked badges
Privacy first

Your health data is yours. Full stop.

Semly has no servers of its own, doesn't sell data, and shows no ads. Everything you log stays on your iPhone, unless you choose to export it or sync it through your own iCloud account.

100% private

No accounts, no servers of our own, no third-party analytics or advertising SDK. Ever.

Face ID and a passcode

Protect access with Face ID, Touch ID, or your own passcode, stored with a random salt and PBKDF2 — never as plain text.

iCloud, if you want it

Sync between your own devices with your own iCloud account, if you choose to. You decide, with a real switch in Settings.

And more

Your data, in whatever format you need

Export, sync with Health, and use the app in whichever language you prefer — with zero friction.

Excel, CSV, PDF, JSON

Export your full history in whichever format you prefer, whenever you want, and share it with whoever you choose.

Health integration

Read and write your weight to Apple's Health app, with no duplicate entries and no extra work.

Spanish and English

Switch the whole app's language instantly, with no restart, from Settings → Language.

Semly is now available on the App Store

Download it for free on iPhone and iPad. If you have questions or feedback, get in touch.