In Sway, you're charged with guiding a ragdoll-like creature through a series of stages, avoiding obstacles and collecting star icons on the way to each level's exit. Using both thumbs, you control your character's arms. By pressing on either the left or the right half of the screen, you'll make your character grab on to whatever object is in the background. After a successful grab, moving your thumb left and right will make the creature swing back and forth. The idea is to constantly transfer movement from one thumb to the other in order to make your character swing through each level.