Displays Real-time Data For Smartphone's Fitness Apps Remote For Fitness Apps & Music Bluetooth Smart Heart Rate Monitor Designed For Sports Ruggedized Echo Utility App Water-resistant (ipx7) Ultralow-power Technology Runs Off A Replaceable Cr2032 3v Coin Cell Battery 6-month Battery Life On High 11-month On Low Compatible With Iphone 4s 5c & 5s Ipod Touch 5th Gen Or Higher Ipad Mini & Ipad 3rd Gen Or Higher Supported By Fitness Apps Including Strava Mapmyrun & Ismooth Run High-resolution Display Allows For Superior Readability In Varying Light Conditions Especially Bright Light 128 X 128 Pixels Backlight Invertible 4-button Tap Screen Customizable Buttons Function To Meet User's Needs Watch & Activity Modes Blue