If you've rooted your Android phone, you probably have flashed a ROM or two. Or 20. If you haven't, you will. That's how it works; you get sucked in and its too much fun to quit. While Nandroid backups from a custom recovery are great for a full system restore, what about the equally important things like migrating text messages over to a new ROM? Or all those bookmarks you've collected? Or God forbid you lose your Angry Birds save with all gold eggs and three stars!
Android Central forums member PvilleComp has you covered. He's laid out a very nice post that explains all the whats and hows of backing up your data, including whats safe to re-use and what isn't. If you're new to the whole custom ROM game, or just were never sure what is safe to do and what isn't, this one is for you. And you seasoned experts out there -- don't be shy -- you can jump on in and lend a hand if needed. We're one big happy family.
Hit the source link below for the great tutorial.
Source: Android Central forums