How can I know which GUID represents which app in my iTunes backup of my iPhone?

Solution 1:

This used to be possible with Erica Sadun's mdhelper program. Unfortunately, it looks like something has changed in the way Apple stores backup files w/ iOS 4.2, and the program cannot achieve the same results (since it finds no mdbackup or mdinfo files).

On the bright side, a new tool named iPhone / iPod Touch Backup Extractor has emerged. It correctly translates the GUIDs to names in my iOS 4.2 backups, and allows the files for each app to be extracted together.