If you use a case, buy case-friendly glass. It stops a millimetre or so short of the curve at the screen's edge, so the case lip can't press on it and lever it up. The visible border is normal. If you never use a case, edge-to-edge glass looks neater.
How it works
Most phone screens are flat in the middle and curve slightly into the frame at the edges. Case lips wrap over that curved edge. A protector that reaches into the curve sits under the lip, and every time the case goes on or off it gets pushed. Case-friendly glass stays on the flat part.
Case-friendly vs edge-to-edge
| Case-friendly | Edge-to-edge | |
|---|---|---|
| Coverage | Flat area; thin border visible | Almost the whole front |
| With a slim case | Stays put | Often lifts at corners |
| With a rugged case | Stays put (check lip) | Usually lifts |
| Without a case | Edge area exposed | Neater, more protection |
| Dust at edges | Less | More (edge collects lint) |
Thin phones show a bigger gap
On very slim phones like the iPhone Air, the flat part of the display is narrow, so case-friendly glass leaves a more obvious border. It's still the right choice with a case.
Checking your case
Put the case on the bare phone and look at where the lip meets the screen. Hold the protector (backing still on) over the screen: if its edge would sit under the lip, look for a smaller protector or a case with a lower lip. See protectors with MagSafe cases.
Questions people ask
Why is my screen protector smaller than my screen?
It's case-friendly: cut to the flat part of the display so a case lip can't lift it.
Can I use edge-to-edge glass with a case?
Sometimes, with a low-lipped case, but corners often lift. Case-friendly is safer.