Hi there. I have jailbroken my iphone 4 5.0.1 tethered and done the rebot correctly and whatnot. My appstore, youtube, and safari no longer work now. I did a full restore of the ipsw creating a new backup and the apps worked prior to the jail break. They also worked right afterwards too. Are there any specific apps/tweaks within Cydia that will cause the stock apps to not work and crash upon launch? Please help... Thanks so much.