How do I remove a screen protector safely?

Removing a protector is straightforward when it's intact and requires care when it isn't. The technique differs, and using the wrong one on cracked glass is how people end up with fragments and cut fingers.

Warm it first

Silicone adhesive softens with heat. Thirty seconds with a hairdryer on its lowest setting, held well back and moving constantly, is enough to change the protector from something that tears into something that releases cleanly.

Don't overheat the phone. If the back is uncomfortable to hold, stop. On a hot day you may not need heat at all.

Getting under an edge

Use something non-metallic. A plastic card, a guitar pick, a fingernail or the plastic tool included in many kits. A metal blade will mark the display bezel and can chip the glass beneath.

The gentlest method, and the best one on a large tablet, is dental floss: work a length under one corner and draw it across the surface in a sawing motion. It follows the adhesive line without applying point pressure anywhere.

Pull slowly and shallow

Once a corner is lifted, keep the angle low and pull slowly. A fast pull at a steep angle concentrates stress along one line, which is what causes tearing on film and shedding on cracked glass.

If it resists, apply more heat not more force.

Cracked glass needs taping first

This is the important one. Cover the entire face with parcel tape or wide packing tape before you start, pressing it down firmly over the cracks.

The tape holds the fragments together as a single sheet, so the protector comes away in one piece instead of shedding slivers into your fingers and onto the desk. Skipping this step is how people cut themselves.

Work gloves aren't overkill on a badly shattered protector.

Cleaning up afterwards

Residual adhesive comes off with the alcohol wipe from your new protector, or a microfibre cloth barely dampened with isopropyl alcohol. Work from the centre outwards and keep liquid away from the earpiece grille and ports.

Let it dry completely before fitting the replacement. Trapped solvent shows as a haze under the new protector and can take days to clear, and it's indistinguishable from a fitting fault at the time.

What not to do

Don't use acetone, nail polish remover, or any solvent stronger than isopropyl alcohol, several will attack the oleophobic coating on the display itself, permanently.

Don't pry from the middle. There's nothing to lever against and you risk pressing on the display.

Don't reuse a protector that has been off for more than a few minutes. The adhesive collects airborne dust immediately and refitting it traps every particle.