From Google Play Store:
Field Trip is your guide to the cool, hidden, and unique things in the world around you. Field Trip runs in the background on your phone. When you get close to something interesting, it pops up a card with details about the location. No click is required. If you have a headset or bluetooth connected, it can even read the info to you.
Field Trip can help you learn about everything from local history to the latest and best places to shop, eat, and have fun. You select the local feeds you like and the information pops up on your phone automatically, as you walk next to those places.
Currently, it is only available for US users, so just go to Play Store to download this.
For non-US users, here is the APK.