I am having periodic issues with some apps like Facebook & Twitter freezing for several minutes or sometimes until I do a hard reset. Is this an issue with iOS 8.0.2 or a problem with my iPhone 6?
It's possible, but are you using versions of the listed apps that have been updated for iOS 8?
I can't help but believe that major apps like Facebook & Twitter are optimized for iOS8 with the most recent updates...but I'm not 100% certain. How would I know for sure if an app is optimized?