I have a iphone 4s, ATT, and today while typing an email my phone started flickering white like it was glitching all through out the screen. Not in any particular area, just all over. It did this for about 5 minutes then it just stopped. Since then it has done it every so often. I tried to screen shot it to upload a photo, however the screen shot came up normal, with out glitching. Anybody else have this issue? Just curious of what this could be. Thanks!