Hi,
I just upgraded Android wallet and noticed, that my old balance disappeared.
It is still showing my old address under "Your addresses", but my new balance is zeroed.
Any way to get it back? Of course I had no backup.
I think upgrade should not zero the balance in any way.
Did you backup your wallet?
Do you have transactions on main screen?
If it shows you your old address, try to reset blockchain in Menu -> Settings -> Diagnostics -> Reset block chain
but before backup your wallet in Menu -> Safety -> Backup
update doesn't touch data (that holds info about your wallet including balance)