How to use your iPhone as a level

Using Apple’s built-in level

Apple keeps the level inside its Measure app. Apple’s guide describes it like this (Apple):

1. Open Measure. It’s in the Utilities folder.
2. Tap Level.
3. Hold your iPhone against the object you’re checking, or lay it flat on a surface. The screen shows how many degrees it is off level.

Apple notes that the measurements are approximate (Apple).

Using The Measure App’s bubble level

The Level tool in The Measure App gives you two faces, and keeps the one you pick rather than switching on its own:

• Level shows a horizontal vial. Stand the phone on the edge you’re checking, such as a shelf or a picture frame.
• Surface shows a round bullseye. Lay the phone flat on a table, a floor or an appliance.

The reading is in tenths of a degree. The crosshair button sets the current position as your zero, and the reset button takes you back.

Getting a steadier reading

• Check the phone sits flat. A camera bump can tilt a phone lying on its back. Setting your own zero on a surface you know is level takes that out.
• Hold the edge, not the middle. Press the phone’s long edge firmly against the thing you’re checking.
• Turn it round. Read once, turn the phone end to end and read again. If the two readings differ, the difference is the phone, not the surface.

For angles of a corner rather than tilt, the Angle tool uses the camera instead, and our roof pitch calculator converts degrees to pitch and percent slope.