The video shows the map selection screen, you see your friends and the level they are currently at, it then show it being played on the following Levels:
1 = Tutorial showing 'swap' move.
2 = Tutorial showing 'connect' move.
38 = Difficult level, whilst playing you have to get a bomb drop to the bottom of the screen (without directly touching it) with a limited amount of moves. Martians will raise their shields and become invisible if they don't move every so often - see see their colour you have to smash the shield or make them move.
21 = Frantic level with lots going on.