Front camera, rear camera and flash test

When to test the cameras

Test the cameras when you look at a used device, after a screen or back glass replacement (the cameras often have to come out), and when photos suddenly turn blurry or spotty. Wipe the lenses first, then open each camera in turn, including the front one.

Common faults and their causes

• No picture, black screen: a loose camera cable or a dead camera. On iPhone, a non-genuine camera may work but the device will list it as an unknown part in Settings.
• Won't focus, shaky or smeared photos: a broken autofocus or optical stabilisation (OIS) unit, common after a drop or long use on a vibrating motorbike mount.
• Fixed spots, haze or streaks: dust or moisture inside the lens assembly, or a scratched lens cover.
• A rattle when you shake the phone: on many phones that's the stabiliser moving, not a fault. It only matters if photos are also shaky or blurry.

Note that a browser can only open some of the cameras. On a phone with several lenses (ultra-wide, telephoto), also try the built-in Camera app and step through each zoom level.

What to do if you find a fault

• Clean the lens and remove the case (a misaligned case can cover part of a camera), then try again.
• Photograph something plain and bright, like a sheet of paper or the sky, to make dust spots obvious.
• Just repaired: see checking a device after a repair.