Iphone screen is black and won't come back even though it still works?

My iphone dropped and the screen sort of popped up in the front and i tried pushing it back in but then the phone turned black and it still works because i can still hear it and i tried taking it to apple and they replaced the display and the screen is still black! If anyone has a suggestion on what i should do i would really appreciate it or even a way i can get a cheap thing i can use to try to save all my data because i can't plug it into itunes and use icloud because my phone always asks for me to trust the computer and i currently can't do that because the screen is black if anyone knows what i should do it would be much appreciated!

Try pressing the power button and home button for 10 sec it might switch on.

You need to Hard Reset your device, after that do install Leo Privacy Guard so that you can secure your device totally.