I have a very vanilla, AT&T 3G iPhone (4.2.1), and I have 2 problems: 1. Over the past 3 months or so, I've noticed it running slower and slower. It's most apparent with Mail and Safari, but I've noticed it across the board. It's like there's spyware running. Is there something that I need to do to "clean" it? 2. Also, over the past 3 or 4 weeks, it has developed a very nasty habit of occasionally aborting the app that I'm running (no error message) and giving me a black screen. When I then press the Home button, it brings up the base Home screen and I have to start all over with what I was doing. Do I have a bug of some sort, or is the phone going bad? Any help would be greatly appreciated!