When I switch platform between devices in unity 4.1, the entire app comes crashing. There is a bug report with a unity dev reproducing it using NGUI examples here:
[link removed]
I thought if you don't know of this already, perhaps you would like to, since this makes unity 4.1 unusable to a number of people, I presume, because obviously we aren't going to stop using the best ui kit out there for a bump in the unity version!