Gorilla Glass and other similar competitors have given us quite tough touchscreens on our mobile devices, and although it doesn't mean that they won't break when they fall on hard surfaces, at least they shouldn't get scratched very easily, which used to be a big problem in the past with phone screens.
Next year, or even by the end of this year, we're also going to see a much tougher Gorilla Glass 3 screen, that should make new smartphones even more resistant to scratches and drops. The new Gorilla Glass composition has been completely remade, and they've improved its durability at the atomic level.
But if you think this is exciting, then you've seen nothing yet. On the horizon there's something that could leave Gorilla Glass in the dust: sapphire-based screens. Manufactured sapphire is used as transparent armor for military vehicles. So you can imagine it can be pretty tough.
Sapphire is actually a crystalline form of aluminum oxide, that could make phones' screens 3x harder to break and 3x more resistant to scratches than current Gorilla Glass screens. It's the reason why Apple uses it for their iPhone 5 cameras, too. There's only one small problem, though. Right now it costs about 10x more than Gorilla Glass ($30 vs $3), but in a couple of years that price could drop to $20, or perhaps even lower, depending on how fast the competition for this type of material will heat up, in the mobile device market.
An alternative could be to laminate a cheaper material (like Gorilla Glass or a competitor glass material) with a thin layer of sapphire, and you could get much of the benefit of pure sapphire, but for a much lower price, at least as a transitional period, before we're using sapphire for everything.
I'd certainly like to see in the future a whole phone made out of this material. We're now starting to see more and more glass-based smartphones, which are not the toughest in the world, but sapphire could actually represent a compelling material choice for them, even over aluminum or some other metal, without any downsides for signal strength. But that is going to cost a lot right now, and I don't see many manufacturers trying it out soon.
I just hope one Android manufacturer gets to try it before Apple, because now that they're using it in cameras, I'm quite sure Apple will be watching the price of this material like hawks, and as soon as they think it's reasonable enough to use in their phones, they'll use it, probably a full year or two before others, considering the profits they make on their phones. Samsung is the second most profitable smartphone company, but I don't see it trying it too soon, considering how big fans of plastic they are right now.