iPhone Touchscreen Not Working
The Problem: Your phone’s screen has stopped responding, or it has frozen and is stuck on a black screen.
The Fix: The first thing you should do is try a force restart. We’ve detailed how to do that above (anchor link). If that doesn’t work, try charging the phone for up to an hour. If you still don’t see the charging screen, or you see the connect to power screen, try cleaning out charging point and headphone jack, check the USB cable and the wall plug.
If your screen is cracked and has stopped responding, it’s likely to be a hardware problem – meaning you’ll need a new screen. Apple is famously finicky with its warranties, so if they won’t fix it, try an authorised Apple reseller. They often fix screens for less than Apple, though you might lose some functionality (force touch, for example).