GasBuddy. finds the least expensive gas in your area and not only gives you the name of the station, but it's address, and if you tap on the entry, it will show you all the prices for each grade offered as well as a mimi-menu that let's you get direcions too. You can use either your zip code, or just tap the "Get locations near me" icon. It also allows you to udpate their data base if you get to the station and the prices are more, or less than those listed. Great app.

Poynt is another useful tool for finding food, and entertainment where you are.