Transform your iPhone into a powerful cycling computer with the Wahoo Blue Speed Cadence sensor for iPhone 5, iPhone 4S, iPod Touch (5th generation), iPad (3rd and 4th generations)! The Wahoo Blue SC is the world's first Bluetooth Smart (4.0) cycling speed/cadence sensor made for iPhones and iPad. This sensor and the free Wahoo Fitness App transform your iPhone into a powerful cycling computer. The Wahoo Blue SC connects wirelessly to your iOS device and tracks your cycling speed, cadence, and distance through the free Wahoo Fitness App. The Wahoo Blue SC's odometer functionality tracks the lifetime distance of your bicycle and stores the data in the device. Whether you ride with or without your iPhone, as long as you have your Blue SC you will always know the total mileage of your bike. Using the free Wahoo Fitness Odometer App, you can sync all your data once in range of your iOS device and see the lifetime mileage of your bike by week, month and year. Additionally, Wahoo's open API allows other popular Apps, such as Cyclemeter and Strava to work with the Wahoo Blue SC. This device works with the iPhone 5, iPhone 4S, iPod Touch (5th generation), iPad (3rd and 4th generations).