This simple iOS app is adapted from Apple's CoreBluetooth: Heart Rate Monitor sample app (a Mac app). http://developer.apple.com/library/mac/#samplecode/HeartRateMonitor Use freely. Tim Burks
mareathj/iOSHeartRateMonitor
Simple iOS heart rate monitor app. Uses Bluetooth LE. Based on Apple's Mac HeartRateMonitor application. Requires iPhone 4S or new (2012) iPad.
Objective-C