After I updated to ICS on my DROID4, it ran terrible, slow, lots of force closes or just plain crashes, heating up, fast battery drain. The advice I tried which I found on here was a godsend and I want to recommend it plus add my own:
DO A FACTORY RESET after installing ICS and START FROM SCRATCH-DON'T RESTORE. I didn't do something right and my apps didn't restore like when I switched from DROID3 to DROID4. I had to find them all manually, but all the app info, per app, were on my SD Card and app info was still there when reinstalled. This ended up clearing away junk apps, email, etc, so not restoring worked out. Plus I set up from scratch with groups on home screen, etc. The only thing I really miss is the old widgets, but it isn't terrible.
My DROID4 works awesome now! No overheating, though the battery drain still sucks, even when I found a switch/app to turn 4g off. No spontaneous power resets, no crashes, no force close/wait pop ups and it just runs smooth and fast.
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