I am not updating to iOS 8.3 because of multiple threads in Apple support communities opened anew after iOS8.3 upgrade by users.
1) The cable not recognized issue - here
and 2) issue with wifi being intermittent - here
If looking for complete list of fixes in iOS 8.3 look here - official Apple page.
Point is Apple should get into security only fixes for devices like iPhone 4/4S instead of keeping them feature heavy and possibly issues like this. I swear by the performance of iOS 7.1.2 on iPhone 4S[which i don't have anymore]. iOS 8.x has been comparatively slower but usable for certain.