If I have a text message typed but not sent and the phone shakes (hand on the back of the phone, not the front) it sometimes sends. If I am on the home screen and the phone shakes enough it sometimes dials someone. It will especially so this if I have someone's text message window open. It is like it "presses" the phone icon by itself.
The screen is cracked a little at the bottom right side of the screen. There is not a screen cover.