Surface and edge measurements, offline.
Place the back of your device on a surface in Surface mode, or stand it upright with the bottom screen edge along the surface in Edge mode. Remove any case that prevents stable contact. Camera bumps can affect flat contact.
Set zero on a known level reference or another surface to compare relative angles. Clear zero restores the gravity reference. Changing measurement mode or screen orientation clears calibration and hold. Backgrounding stops the sensor and clears the held value. Hold freezes the displayed reading.
Surface and edge measurement, calibration and hold. The optional Measurement Toolkit is a one-time purchase for target angle and tolerance, named local records, and text report sharing. No subscription or advertisements.
Surface mode shows the total tilt between the current and reference gravity vectors. The two-axis bubble saturates at 10° in each direction; the number continues to show the measured angle. Edge mode shows a signed angle from −90° to +90° and treats parallel edges as equivalent. Keep the screen upright for Edge mode; keep the back roughly horizontal for Surface mode.
Measurements require a compatible physical iPhone or iPad. A simulator has no motion sensor. Reposition the device when asked; reopen the app after a sensor error.
Results are estimates affected by device sensors, case, camera bump, contact and calibration. This is not a certified precision instrument. Compare against a known reference before relying on a measurement.
Records stay in the app on your device. Share sends only the report you choose through the system share sheet. Swipe a record to delete it and confirm. Deletion is permanent. If a data file cannot be read, the app preserves it instead of overwriting it. Export important measurements before deleting the app.
Open Settings → Restore Purchase using the same Apple Account. Internet access is needed for App Store purchases and restore, but measurements work offline.