Like others I am having the issue of android apps not being able to use the Internet over 3G. The other issue I'm having is that the apps are extremely laggy and sometimes unusable. I had none of these issues before 10.2.1 with my sideloaded apps.
How did you do the update? OTA?
If you did you need to sideload them again. Delete and reinstall the Android apps and see if that helps at all.
I loaded the 2141 as a leak with Sachesi and my Android apps are no different than before.