I have the same problem all the time, I've been to my carrier and Samsung store at Best Buy, no one has an answer, I was told wait for lollipop to come to see if it fixes it, that it might just be the way the app is interacting with kitkat. But if it still does it they're going to try to install a new Kendal version I believe is what it is, on the phone and wipe out the one that's on it, basically start from scratch again since factory reset hasn't worked. Hopefully lollipop does the trick though, fingers crossed