The mechanics of Draw Story! are very simple. Throughout each level the game requests you draw a certain object. You'll have to do that by lightly dragging your finger tip around the screen just as you would with a pencil when drawing on paper. As you complete your drawing, the game's AI will try to figure out what it is, and once it does -- it's onto the next challenge!
With each victory you earn coins to invest in unlocking new color palettes. While that won't make much of a difference in terms of mechanics, it does add a bit of flare to your games.
One of the most interesting features of Draw Story! is its discreet but effective multiplayer mode where you get to watch real time as the creations of players from around the world unfold before your eyes.