Mobile tests
Tests built for phones and tablets. Open this page on the device you want to check — most of these need the hardware in your hand.
Also worth running on a phone
These live in other sections but work just as well on a handset.
About these mobile tests
A phone concentrates every sensor into one sealed slab, which makes a browser useful for narrowing down a fault before you book a repair. A screen with an unresponsive strip, a compass that will not settle, or auto-rotate that has stopped working are all visible from a web page, and none of them need an app to diagnose.
The touchscreen tests are the ones worth running after a drop or a screen replacement. Sweeping the whole surface finds dead zones a digitiser has stopped reporting, and the multitouch test shows how many simultaneous points the panel reports — a number that drops when a digitiser is damaged, and one that cheap replacement screens often get wrong.
The motion sensors sit behind a permission prompt and only work over HTTPS. On iOS you also have to grant access explicitly each session, and Safari will refuse entirely if Motion & Orientation Access is switched off in settings. If the readings stay flat on a device that should have the sensor, that setting is the first thing to check.