How does a compass work on a smartphone?

This is a really good feature of a smartphone that not too many people know about.

I was asked to make a video on this (seen above), but I figured it would also be good to put together an article about it, as this is good information to know.

Ordinarily, the way a plain magnetic compass works is by use of a magnet that allows something to move. If it's a traditional handheld compass, the arrow can be moved by the magnet to tell you which direction you're facing. If the compass is made for marine or car use, there is a ball floating in liquid, and the magnet can move that to indicate direction.

Smartphones have no moving parts, so the way its internal compass works is different.

All modern smartphones have a magnetometer in them. But since that doesn't move, it is assisted by the accelerometer sensors in order to tell you which cardinal direction (as in north, south, east or west) you're facing.

You can turn off location (GPS), data and Wi-Fi and the compass feature of a smartphone will work since it requires no radio signals to function. All you need is a compass app. For Android, the app I prefer is GPS Test Plus, available in the Google Play Store. Apple iPhone does not have that specific app, but a search for "compass" in the app store will get you a compass app that more or less does the same thing.

There are a few very good reasons why it is important to know about the smartphone compass.

Published 2020 Nov 17