This app will only work if your device supports ANT. Some devices support ANT+ out of the box. For a list of them visit: Another way to use ANT+ is via an USB dongle. If you have an ANT+ compatible device you can use this app to find Chirp geocaches. Just start the app, turn Chirp search on and find a Chirp. Your device will warn you as soon as a Chirp is found.