Pebble is the first watch built for the 21st century. It's infinitely customizable, with beautiful downloadable watchfaces and useful internet-connected apps. Pebble connects to iPhone and Android smartphones using Bluetooth, alerting you with a silent vibration to incoming calls, emails and messages. While designing Pebble, we strove to create a minimalist yet fashionable product that seamlessly blends into everyday life. Pebble connects by Bluetooth to your iPhone or Android device. Setting up Pebble is as easy as downloading the Pebble app onto your phone. All software updates are wirelessly transmitted to your Pebble. Compatibility iPhone 3GS, 4, 4S running iOS 5 or any iPod Touch with iOS 5. Android devices running OS 2.3 and up. Works great with Android 4.0 (Ice Cream Sandwich)!