If you are out and about and need to find a place to eat, then Urbanspoon is an essential app to have installed on your android device. You can easily find restaurants of all price ranges and cuisines, and quickly read user comments and reviews. One of the most unique feautures is the "shake" function, allowing you to enter some simple preset criteria, and have Urbanspoon chose a eating venue for you.
Int he words of the developer:
Can't decide where to eat? Urbanspoon can help. Shake your phone and Urbanspoon suggests restaurants near you. Keep shaking until you find a restaurant you'd like to try.