Oh, yes, and never EVER do anything without backing up properly.
what is the best back app your using?
how does it work when something goes work? where does the backup file gets saved? what does it save? phone numbers? etc..
thanks for the help
I'll answer which questions I can actually understand there
First off, one needs to understand backup up ROMs, data and caches. This is a function in either recovery (CW or SP). When creating a nandroid backup, it will be stored to your SD card (although the directories are different for SP and CW).
Never flash a ROM without creating a nandroid backup
Now, as far as other backup utilities, specifically for apps and settings, the best option I've found is Titanium, there are both free and paid versions. The paid version is worth it, helps the dev, is inexpensive and definitely a good thing to have. Alternately, there is also some backup functionality in Astro, although Titanium will back up apps and settings, while Astro will only back up apps.
Now, as to what to do when something goes wrong, that really depends on what happened. It may be as simple as restoring a backup from recovery, or it may involve re-flashing the recovery using RSDLite and .sbf files. There are a lot of variables there, and this is why I say that people need to be aware of the various utilities (such as RSD), be prepared to- and know how to- use them. These advanced utilities used to be the only way to root your phone, so people had to get familiar with them up front.
Unfortunately, now that people have access to Easy Root and ROM Manager, it is too easy for somebody to get in over their head without fully understanding what they are actually doing to their phone and how to fix it if something goes wrong.
That's just one man's opinion, and is not a criticism of people who have used either utility. However, the number of posts asking for help as they have screwed up their phone with this stuff has definitely ticked up over the past week or so. I blame that on innocent lack of preparation and research.
Heck, the Easy Root website has lot of PayPal links, but
nowhere does it mention that rooting will void your warranty or even explain what rooting actually does-or the potential risks. That's just irresponsible in my mind.