You are trapped in the middle of a frozen lake that is so smooth that there is absolutely no friction so there is no way you can grip the ice. There is also no wind to propel you along. The only thing you have on you is a mobile phone, but unfortunately it has no reception so you can’t call anyone for help. How do you get off the ice before you freeze to death?
Quite simple really, throw away the mobile phone and while it glides off in one direction, the kick from the throw will propel you in the opposite direction (while the kick from a throw is not quite as large as the kick from firing a gun, it is still effective enough). Since the ice is frictionless you won't stop until you reach the shore. Then you can always walk around or take a run up and slide back across the lake to collect your phone.