If you've taken the time to peruse the threads on upgrading to iOS 8.x, you'll find plenty of users complaining about this newest version.
BUT, you really need to provide MUCH more information on your issue(s): 1) What iPad model do you own; 2) What iOS version did you upgrade from; 3) How far along in the 8.x upgrade have you gone (current release is 8.1); and 4) What specific problems are you having? This might help us to reply - Dave