Regarding the black sign appears in cell "android.process.acore problem" It Happened to Me. I gather it was because a little wipe the phone that was slow and I have things importantes.para draft operation.
what I did, which is very simple, but maybe someone can serve (The phone is a Samsung) I went to Menu settings - more - Application Manager - disabled (and saw the last thing he had off and went back to activate)
greetings. thanks to all