You shouldn't need to factory reset, just update and everything should work ok.
"Should"
In reality major updates often cause some little issues that require a factory reset to fix. I would suggest backing up anything important and running the update. If everything is smooth and fine then great, if it's a bit niggly then FR.
EDIT\\ If you're rooted the answer is a bit more complicated than this...
"Should"
In reality major updates often cause some little issues that require a factory reset to fix. I would suggest backing up anything important and running the update. If everything is smooth and fine then great, if it's a bit niggly then FR.
EDIT\\ If you're rooted the answer is a bit more complicated than this...