Open smartypins.withgoogle.com in Safari. You may want to push the Add to Home Screen button to make it look like an app for later use. Click Start a new game to begin playing.
Push the arrows to learn more about how the game works, and then hit Go!
Begin playing by reading the questions as they appear at left, and then drop the pin when you feel like you know the answer.
Continue by clicking Next question.
You may also choose Take a hint if you are stumped on a question. Have fun!