Scratched or cracked the screen of your iPhone, Android smartphone, BlackBerry or Windows phone? All is not lost. Here's how to fix a cracked, broken or otherwise damaged smartphone screen, covering free DIY fixes, insurance options and other advice.

Broken iPhone

But please be warned, before we begin, that the DIY fixes we cover here carry a small risk of exacerbating the problem, as do all home tech projects; and may simply not work. Polishing or buffing a touchscreen may damage the oleophobic coating, if it has one (the iPhone 5, for instance, does). We've tried to cover all the possible fixes for a cracked/scratched smartphone screen, but these are potential solutions that may be worth trying, not guaranteed miracle fixes.

First of all we'd recommend checking your warranty and the feasibility/expense of getting the screen repaired by the manufacturer or a reputable third party. Think about how serious the crack or scratch really is - could you live with it? Is it worth potentially harming the touchscreen function of the screen, or an expensive repair? Finally, try adding a screen protector, which will help you avoid future damage and is likely to make existing damage less noticeable.

Turn to the DIY fixes if you're desperate - and let us know how you get on!

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How to fix a scratched smartphone screen: DIY fixes

Fix 1: Toothpaste, Turtle Wax and other creams, oils and lotions

Money-saving tech tip or old wives' tale? Smartphone users are divided on that one. Some say the various creams and polishes that promise to smooth out or fill in minor scuffs and scratches in smartphone screens can do no such thing, but others swear by them. In case you skipped over the intro, DON'T ATTEMPT TO POLISH a touchscreen with an oleophobic coating, which is most screens these days. It will remove the coating and leave an obvious patch which will probably look worse than the scratch.

If you decide to give this technique a go, your options include car scratch-removal creams such as Turtle Wax or 3M Scratch and Swirl Remover, toothpaste (bizarrely), various polishes and (according to one highly contentious online tutorial) a blend of egg white and potassium aluminium sulphate.

Seal the ports and buttons of your smartphone with tape to make sure no liquid gets in, then rub your chosen polishing agent into the scratched area using a soft cloth. It may some time and a lot of effort.

Fix 2: Grind/buff/polish/sandpaper the glass

A more drastic solution is to grind the scratches out, using fine sandpaper and/or a dedicated sanding drill attachment (dedicated drill grinders are also available, such as this one). Most advice suggests using cerium oxide, a compound that is mixed with water to create an abrasive polish, and this may do the trick with a cloth alone. One again beware of liquid damage: seal the smartphone as well as you can using tape.

Work cautiously, particularly at first - use the finest and least abrasive sandpapers first, press gently and check the results regularly, in case you're creating an uneven surface or worsening the situation.

Fix 3: Apply a screen film/protector

We discuss preventive and protective measures below, but it might not occur to you that screen protectors make existing scratches less visible. Many of the screen protectors on the market now are surprisingly discreet: some possibilities are listed below.

Tech 21 impact diagram

As well as the cheap screen protectors you can buy in multipacks from the likes of Ebay and Amazon, here are reviews of some premium protectors we've tried:

Moshi iVisor XT screen protector review

Tech21 Impact Shield screen protector review

QDOS OptiGuard-TG for iPhone 5: a toughened glass screen protector

How to fix a scratched smartphone screen: Replace the screen entirely

If the screen is badly cracked it may be obvious that the glass or plastic of the screen isn't salvageable, in which case you need to think about getting the screen replaced entirely. This may be expensive, though. A glass iPhone screen, for instance, will need to be replaced along with its touchscreen componentry - the two elements can't easily be separated - so it's not as simple as buying a suitably shaped piece of glass. Plastic screens may be cheaper.

Check the terms of your warranty (Apple fans would do well to consult our colleague Karen on Macworld, who looks in depth at Apple consumer rights), and contact your manufacturer to see how expensive the process will be. If it's going to cost a lot, remember to weigh up the pros and cons of replacing the screen versus buying a new phone; if the rest of the smartphone is wearing out, or you had your eye on the most recent model (or another brand of smartphone), then now might be the time to switch.

Apple, for one, often prefers to give you a new iPhone than to repair the screen of your existing device (although this policy varies geographically), which gives an idea of how expensive it's likely to be.

Ask the manufacturer if they are willing to send you the new screen or if they insist on doing the repair themselves; the former will be cheaper but don't underestimate how difficult this is likely to be. Inexperienced techies are advised to seek assistance from a tech-savvier friend, or remember that discretion is the better part of valour.

How to fix a scratched smartphone screen: Employ a smartphone repair company

The manufacturer of your smartphone should be your first port of call - they'll be the most qualified to repair the hardware, after all - but don't let them push you into agreeing to the procedure. Third-party repair firms will be able to repair or replace the screen instead, most likely at a significantly lower cost; you just need to work harder to find a reliable company near you.

Search for local businesses, and make sure they're experienced at dealing with your brand of smartphone - we'd suggest looking for evidence on their website or in customer testimonials rather than asking, since an enthusiastic employee may be inclined to exaggerate. Search for ratings and reviews of the service, and ask around for friends' and colleagues' local recommendations. You're entrusting this business with a valuable and easily damaged item.

Burned iPhone

How to fix a scratched smartphone screen: Protective shells, covers, films, cases and bags

Finally, a word on preventive measures to help you avoid scratches and cracks in future.

The major smartphone brands are all tailed by a huge variety of third-party cases and covers, ranging from the lightest and most invisible of screen protectors to heavy-duty cases made for builders and military contractors. Many smartphone cases are designed to improve your grip, making drops less likely, and most provide at least some protection to the most vulnerable areas - namely the corners of the device and the screen. A raised lip/rim around the screen will stop it striking the ground unless you're really unlucky and it lands face-down on something pointy.

We've had good experiences with protective gear by Tech 21, Proporta, Case Mate and Otterbox (the latter two being particularly strong at the heavy-duty end) but there are a huge range of case reviews on this site and on our sister sites PC Advisor and Macworld.

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