LevelUp let's you pay with your phone. They are offering a free $5 credit. Works on iOS and Android.

- Click here and register (click on "Have Promotional Code" on the bottom)

- Enter promotion code 116634 to get a free $5 credit

- Pay with your phone and use the $5 credit

- LevelUp only works in Atlanta, Boston, Buffalo (NY), Chicago, New York City, Philadelphia, San Diego, San Francisco, Seattle, and St. Louis