The subject above says it all.
How can I fix this? I cannot use google play store, google mail app, etc. Messaging freezes, and the phone sometimes goes black and I have to reboot.
I can't download new apps, a lot of the old ones do not work anymore. My phone worked perfect before I downloaded the new OS.
How can I reset the phone or downgrade? Also is there an option to back up what is on my phone so I can get all of my stuff back when I reset the phone?
Thanks!