Originally Posted by Guich
I advice you to full wipe all for a clean install and you won't have any issue.
However, backup your contacts, sms and other stuff you need before the full wipe.
p.s. Your sd won't be touched.
I'm with this guy^^
Definitely wipe it. And it's good to have things backed up anyway. Once you get used to making your backups you can do a full wipe and rom install really quickly, I do them daily when I'm testing or trying out new builds.
My contacts are in google (gmail) and sync when I sign in at the setup screen, I backup and restore sms/mms and I use titanium backup for my user apps, but google installs most of my apps when I sign in. I also copy my entire sdcard storage over to a folder on my computer about every month or so, just in case something happens. I just select the whole thing, drag and drop it into it's own folder on my PC's hard drive.
We all have different methods, just gotta use a method thats best for you to make restoring after an install easy.
On a sidenote: With a jump in versions like that will you be installing different firmware? I dunno that it's required but if you are then you will get a slightly different answer.
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