How to Use the iPhone’s Compass and Level

Hang a painting or find your way home with your iOS device

Women using digital and analog compass devices.

 Getty Images / Hero Images

All Apple iPhones produced since the iPhone 3G in 2008 feature a digital compass and level, placing a few handy tools in your pocket at all times.

The instructions in this article apply specifically to iPhones running iOS 12 and iOS 11 except as noted, but similar instructions apply to all iPhones beginning with the iPhone 3G and iOS 4.

Using Your iPhone's Built-In Compass

To access the compass, begin by launching the Compass app, which appears by default on all current iPhone models. The application is located on the iPhone's Home screen, but if you deleted it, reinstall it from the App Store for no charge.

Calibrating the Compass

When you launch the app for the first time, you are prompted to calibrate the compass by rotating your phone 360 degrees. To aid the calibration process, follow the onscreen animation that Apple provides. After your device is fully calibrated, you are presented with the compass screen.

Understanding the Compass

Hold your iPhone parallel to the ground with the screen facing up. At the center of the compass is a small circle with a crosshair in the center. Ensure your phone is parallel to the ground by tilting your hand to align the crosshair with the center of the compass.

A small red arrow, situated above the letter N, always points north, while a long, bold white line at the top of your iPhone screen notes the current direction that your iPhone is facing.

Compass directions are typically expressed in degrees. Infer your course by either seeing what number the long, bold white line at the top of your iPhone screen aligns with on the outside of the compass circle or by referencing the specific number at the bottom of the screen. The current degree your iPhone is facing updates as you rotate your device. The app also showcases letters indicating the four cardinal directions.

Compass Tips and Tricks

To keep a close eye on the way you are headed, face your destination and tap the center to establish a line of travel. As the compass moves away from that line, you see a red arc spread between your intended heading and your current course. Adjust your path to return to the chosen course. To dismiss the arc, tap the center of the compass once more.

iPhone screens showing how to select and use the Compass app

Depending on your location, you may also see additional information noting your GPS position in longitude and latitude, current geographical location, and your elevation above sea level at the bottom of the screen. This information is not available in all areas.

Using the iPhone's Built-In Level

If you plan to hang a shelf or painting, you can use the Compass app's level function (in iOS 11 and earlier) to ensure that whatever you are hanging isn't tilted. In iOS 12, Apple split the measure function off into its own app, appropriately named Measure, but the functionality remained unchanged. To use it, open the Measure app and tap Level at the bottom of the screen.

Calibrating the Level

After you tap Level, calibrate the app with a point that you already have deemed flush. A digital level can then note how far off your item is from being perfectly aligned with the original surface.

As an example, if you are hanging a painting on the wall and want it to be level with the floor, you place your iPhone flat against the wall, which tells the device you are working on a vertical axis. You then move the iPhone either to the top or bottom of the wall so that the device's edge is touching the ceiling or floor line; both the floor and ceiling are considered to be level.

Man and woman hang up a painting on the wall.
 Getty Images/ Chris Ryan 

You'll see an indication of how far off level the phone is. Adjust the phone's position until you are satisfied that your device is in a position that you consider level, and tap the screen. It turns green and displays the number 0. Your iPhone's level function is now calibrated. You must recalibrate your level each time you switch axes or align something differently.

The vertical Measure app calibration screens

Positioning an Object

Place your calibrated iPhone against an object such as a picture you are hanging on a wall. Rotate the object left or right while keeping the iPhone pressed against it. The number on your iPhone screen changes depending on how far out of level alignment your object is in relation to your initial calibration.

Adjust the object and the iPhone until the number 0 displays on screen indicating it is level. If you see other numbers, those numbers, expressed in degrees, indicate how far the object is from being level. Continue to rotate the object and phone in the appropriate direction to bring the number back to zero.

Measure App Tips and Tricks

At any time in the leveling process, you can tap the screen to recalibrate your device if needed. When you measure in the vertical axis the screen presents you with two small lines on the left and right sides of the screen. When you measure in the horizontal axis such as on a flat shelf, the screen shows two circles instead.