As the title suggests, since installing IOS 4.3, I can no longer use any of the following: Safari - opens, but then crashes back to the home screen as soon as I try to load a site. Mail - Downloads email ok, but when I try to read it, crashes back to the home screen. Youtube & App Store - Open for a second, then crash out to the home screen. All third party apps seem to work fine, for example I can browse the web using Opera. I've tried syncing, resetting, updating all my apps (App Store works fine through iTunes), restoring through iTunes, I'm pretty much out of ideas! I've done lots of Googling, but usually people seem to have problems with third party apps, mine is the opposite way around. I haven't Jailbroken my phone, so there shouldn't be anything dodgy on there. I have a 16GB 3GS.