As you might tell from the name, this is a new minimalist kind of tower defense app. You have a single set of unique turrets which can only be placed at three locations. Click, drag and drop to move your turrets at will. Dropping it onto another turret will make them swap places. While carrying a turret, it will fire at just one third its normal rate.
Each turret is best at dealing with a specific enemy type. Place and move them with a keen eye and a swift hand to protect those nips!
EXTRA CHALLENGE: invent a plot for this thing and post it in the comments. May the best person win.