60beat Heart Rate Monitor for iPhone, Android & ANT Plus Devices, Black Works with iPhone 6s, 6, 5s, 5c, 5 and 4s (and plus versions)-be sure to use the most updated 60beat app in app store Works with over 100 running, cycling, walking, HRV (heart variability) and wellness apps Including MapMyRun, Runmeter, Endomondo, LogYourRun and RunKeeper Dual technology: works with ANT + (Garmin) and Apple watch, connects to ANT + compatible watches Android on galaxy S4, S5, S6 and other androids using OS 4.3 or higher