How to use your iphone 4s as a heart rate monitor

In a previous SnapGuide I outlined how to use Ant+ devices, I have since upgraded to Wahoo's Blue HR chest strap. The Blue HR leverages Bluetooth 4.0 on the iPhone 4S.

Available at most Apple stores for $79.99 (US)

The advantage of using the Blue HR over an ANT+ chest strap is that a dongle, such as the Wahoo Fitness Key ($70) is not required. The Blue HR pairs with your 4S using low energy Bluetooth.

Easy as 1 - 2 - 3, Moisten the electrode pads and wear the chest strap. Launch a compatible app on your 4S, such as Runkeeper, Cyclemeter, MapMyRide., etc Then Pair the Blue HR & commence exercising

Pairing screen in the Wahoo Fitness app

Pairing screen in the Cyclemeter / Walkmeter / Runmeter apps

You only have to pair the Blue HR with a given app once. The next time you use the blue HR moisten and wear, launch the app and within seconds you Heart Rate is being recorded on your iPhone 4S. MAGIC

You no longer need a Polar HRM, $80 for the Blue HR (user replaceable battery) and a free app gets you all the functionality of a dedicated HRM plus real time audio updates & multiple export options.

Use Case for Blue HR over ANT+ solutions: 1. Outdoor activity where the GPS tracks speed/distance & Blue HR tracks HR. Note-until there is a BT4 stride sensor ANT+ is better for treadmill tracking.