I have 2 itunes accounts on my computer--my girlfriends & mine--so I'm always having trouble updating my apps through my iPhone. Sometimes she buys the apps on her account & other times I buy them, so when I try to update an app, it says "You are not authorized to do this". Does that mean I have to plug my iPhone into iTunes & go onto the opposite account? Or what do I do? Half the time, i don't even remember which account purchased the app, so any help on how to figure out that whole problem? I just want to be able to update my apps from my iPhone...