QuickDeviceTest Device test / Touch screen test
Touch screen test
Paint the grid with your finger to find spots that don't respond, and put several fingers down to see how many touches your screen tracks at once.
This device reports no touch support; a mouse drag works for a demo, but the test is meant for phones, tablets and touch laptops.
Tips for a thorough check
- Go slowly along the edges and corners; that's where cracks and lifted protectors cause trouble.
- Drag diagonally across the whole screen in one stroke. A gap in the green cells along the line shows a dead band.
- Rotate the phone and repeat: some faults only appear in one orientation because of how the grid is scanned.
Questions
How do I test my touch screen?
Drag a finger across every cell of the grid. Cells turn green as they register. Any cell that won't turn green, or a line that breaks as you drag across one area, points to a dead zone in the digitiser.
How many touch points does my screen support?
Put several fingers down at once and watch "max". Most phones handle 5–10 simultaneous touches. The "device reports" value is what the browser says the hardware supports.
Parts of my screen don't respond. What now?
Remove the case and screen protector (a lifted edge can cause dead zones), clean the screen, and restart. If a band still fails, the digitiser is likely damaged and needs repair.
The screen registers touches I did not make.
Ghost touches are often caused by a faulty charger, moisture or a cracked digitiser. Unplug the charger and dry the screen, then test again.