Why verification matters
A timer-only redemption is an honor system. Honor systems fail the same person twice in a row because the cost of cheating is zero. ScreenFine verifies. The iPhone TrueDepth front camera counts pushup reps using a depth-tracked rep counter that watches your chest distance to the lens. Gym-style cheat moves (head bobs, half reps) do not pass. Step counts come from HealthKit, which the phone has been quietly logging all day. Mindful minutes are timer-only by design, but the trade-off is a longer redemption (10 minutes vs. ~90 seconds for 25 pushups), so the friction is comparable.
What unlocks the apps
You pick one redemption type during onboarding and it applies to every fine. 25 pushups is the default because it is short, physical, and verifiable. 1,000 steps is the alternative for users who cannot do floor exercises. 10 mindful minutes is for users who prefer breath work or have a quiet space. The redemption is the same across every fine, so the contract is predictable: cross your limit, do the reps, unlock. No menus, no decisions in the moment.
Camera privacy
The pushup counter runs entirely on-device. Frames from the TrueDepth camera are processed by the ARKit body-tracking framework, used only to increment a rep counter, and discarded. No video is recorded, stored, or transmitted. The camera permission is required only because ARKit needs it. You can switch to HealthKit steps or mindful minutes at any time if you prefer not to grant camera access.