Why phones have glass backs
Most phones from the last several years have a glass back because wireless charging (and Apple's MagSafe) can't work through metal. The glass is tough, but it's still glass: a fall onto a hard edge, or a drop on its back without a case, can crack it like a screen.
Is a cracked back just cosmetic?
Not quite. A crack across the back:
- can cut: small splinters come away at the edges of cracks, especially near corners;
- lets in dust and moisture: the back is part of the phone's seal, so treat a cracked phone as not water resistant;
- can spread: every knock and every hot day in a car makes cracks grow;
- can reach the cameras: on many models, the camera lens covers sit in or next to the back glass, and a crack there spoils photos (here's what a damaged camera looks like);
- lowers resale and trade-in value: buyers and trade-in programs mark down cracked backs heavily.
Wireless charging usually keeps working through cracked glass, but a badly broken back can stop the phone sitting properly on a MagSafe or Qi charger.
When it can wait, and when it can't
| What you see | What to do |
|---|---|
| A small crack in a corner, nothing loose, phone in a case | It can wait a little; keep the case on |
| Cracks across the back, nothing loose | Fix it soon, before it spreads or splinters |
| Loose or missing pieces, sharp edges | Fix it now; cover it with clear tape until then |
| Cracks around or through the camera area | Fix it now, and have the cameras checked |
| A bulge, or the back lifting away from the frame | Not a crack problem: that's a swollen battery. Stop charging the phone and get it checked straight away |
What the repair involves
How hard a back glass repair is depends on the model:
- On newer iPhones, Apple redesigned the inside of many models (starting with the standard iPhone 14) so the back glass can be removed and replaced as a part.
- On older iPhones (iPhone 8 to the iPhone 13 series, and the 14 Pro), the back glass is bonded to the frame. The repair removes the broken glass from the frame and fits new glass, which takes longer.
- On Samsung Galaxy phones, the back glass is held on with adhesive, so it's softened with heat, removed, and a new back is fitted with fresh adhesive.
Either way, the phone's insides are protected while the glass is removed, and it's tested afterwards: wireless charging, the cameras, and the seal. Your data isn't touched.
Any repair that opens a phone can reduce its water resistance, so treat it as not water resistant afterwards.
Should you fix it before selling?
For a recent phone, often yes: the difference in trade-in or resale value between a cracked and an intact back can be more than the repair. For an older phone worth little, the repair may cost more than it adds. If you're not sure, get a quote first and compare it with what the phone sells for in each condition.
Preventing the next one
A case with a raised rim around the back and the cameras takes almost all of the knocks that crack back glass. Clear cases show off the phone's colour; rugged cases are worth it for work sites and kids.
Sources
Related repairs at Riverlink