I am having a really bad problem in my Galaxy S4, and have been trying to fix it for a full day. Basically, many of the default android apps fail to work. By fail, I mean the screen becomes fuzzy, or completely distorted, and just crashes. The phone also randomly restarts when I use it. Overall, I really can't use the phone. I have attached screenshots of some of the issues I am facing on the phone. I have tried reinstalling Android version 4.2.2, but the same problem occurs. Any help on this matter would be MASSIVELY appreciated!