PhoneFit

Last updated: 7 November 2026

PhoneFit (called LazyFit before version 1.3) is a free iPhone app for short standing workouts, with an optional one-time purchase, PhoneFit Pro. It is operated by Kaifuz Studio. Your workouts, measurements, settings and calendar stay on your phone. There is no account, no analytics, no advertising and no tracking. The one outside service PhoneFit talks to is RevenueCat, which records PhoneFit Pro purchases for us (section 4).

1. What stays on your device

Everything PhoneFit keeps is stored locally on your iPhone:

Workout sessions — a record of each completed workout, such as when it happened, how long it was and the reps counted, stored with Apple's SwiftData on the device. They power your streak and week view.
Body measurements — the weight and tape measurements you choose to log in the Body tab (waist, chest, hips, arms, thighs, calves, neck, shoulders), with their dates, stored with SwiftData on the device. You can delete any entry.
Settings — your preferences, reminder times and the look of the 3D guide (outfit, background, companion pet), stored in UserDefaults. A small part is kept in an App Group container that is shared only with PhoneFit's own Home Screen and Lock Screen widgets, so they can show your progress and start a workout.

We do not have a server that receives this data, and we cannot see it. Deleting the app deletes it (workouts you chose to save to Apple Health stay in Health until you remove them there). If you use iCloud or device backups, your data is included in those backups under Apple's own terms, the same as any other app's local data.

2. Motion sensors

PhoneFit reads your iPhone's motion sensors during a workout to count your reps, keep the tempo, and notice when you set the phone down or pick it up. This data is processed live, on the device, while you exercise. It is not stored and is not sent anywhere.

3. Apple Health (optional)

Apple Health access is off until you turn it on in PhoneFit and grant permission in Apple's Health prompt. If you do:

Read: PhoneFit reads your body weight only, to estimate the calories burned in a session. It reads nothing else from Health.
Write: each completed session is saved to Health as a workout, together with its estimated active energy. Weight and waist measurements you log in the Body tab are also saved to Health; other measurements have no Health type and stay in PhoneFit.

Health data is never used for advertising or marketing, is never shared with anyone, and never leaves your device except through Apple's own Health sync, which Apple controls. You can revoke PhoneFit's access at any time in Settings > Health > Data Access & Devices > PhoneFit.

4. PhoneFit Pro purchases

PhoneFit Pro is bought through Apple's App Store. Apple handles the payment; we never see your payment details, name, email or Apple Account. From version 1.3 the app uses RevenueCat (RevenueCat, Inc.) to record purchases. When you buy or restore Pro, RevenueCat receives the App Store transaction (product, price, currency, date and storefront), tied to a random identifier the app creates on your iPhone. When the app opens it also asks RevenueCat about purchase status; like any internet request this includes your IP address and basic details such as the iOS and app version and language. We use this to see sales and to help if a purchase goes wrong. RevenueCat handles it under its own privacy policy. Workouts, body measurements, motion data and calendar data are never sent to RevenueCat.

5. Calendar (optional, PhoneFit Pro)

If you turn on "Fit into my calendar", PhoneFit asks for access to your calendars and reads the start and end times of your events to find a free 15 minutes for your workout reminder. This happens on your iPhone. Event titles, locations, notes and attendees are not used, and nothing from your calendar is stored or sent anywhere. The reminder itself only says when your free time ends. Turn it off in PhoneFit, or revoke access in Settings > Privacy & Security > Calendars.

6. Notifications

Workout reminders are local notifications scheduled on your iPhone by the app. They are not push notifications and involve no server. You can change or turn them off in PhoneFit or in iOS Settings.

7. Live Activities and widgets

The Live Activity, Dynamic Island and widgets are drawn on your device from the same local data described above. Nothing is sent to us to display them.

8. What we do not do

No account or sign-in.
No analytics, crash-reporting, tracking or advertising SDKs. RevenueCat only records purchases.
No sale of data, and no sharing beyond RevenueCat recording purchases on our behalf.
No camera use.

9. Children

PhoneFit does not ask anyone, including children, for personal information. The only data that leaves the phone is the purchase record described in section 4.

10. Changes to this policy

If PhoneFit's handling of data ever changes, we will update this page and the date at the top before the change ships.

11. Contact

PhoneFit is operated by Kaifuz Studio. For questions about this policy or the app, get in touch through our support page.