Meet the Pingbell: a smart bike bell that connects to your phone, letting you know where you have parked your bike. It uses Bluetooth Smart to tell you if you are getting closer. It is also possible to ping your bike to find it faster. The Pingbell is made of brass and makes a loud sound when you ping it.
Pingbell is compatible with iOS and Android devices. You will be able to track multiple Pingbells and share their location. More information is available here.