My son got ahold of a beta version of iOS7 and after installing it on his phone had issues with locking up. He then restored the old iOS but now his apps won't work. The guy at the Apple store suggested he erase all settings and do a clean restore but I can't be sure which backup to use and if we have a backup from before he upgraded in the first place. He swears he backed up before the initial upgrade but I can't seem to find anything but the last backup. Any suggestions? He is concerned about losing his contacts and memos.