I had my downloaded apps duplicated too. I started uninstalling them one by one... that was taking to long so I performed a reset through hte phone menu. I do not have the problem now after performing the reset.
Reboot did not fix mine, wished it would have....
Re: Lg Optimus G sprint cracked glass
@Schumacherml1 - visist a Sprint Service & Repair store to see if they are able to assist in replacing the glass. If you do not have insurance, it may cost you.