Runkeeper update allows Apple Watch Series 2 & Nike+ users to track iPhone-free runs via GPS | AppleInsider
The Beets BLU heart rate monitor transmits the heart rate through Bluetooth to the iPhone, where an app like Runkeeper logs the data. Heart rate monitor with chest strap, in March 2014
Chest strap Bluetooth with ANT+ 5 kHz uncoded for Runtastic, Wahoo, Strava, Runmetter, Endomondo, Runkeeper app for Android such as Samsung S3 / S4 / S5 / S6 / S7 / S8 /
How to Pair Your Heart Rate Monitor – ASICS Runkeeper Help Center
RunKeeper: Now with auto pause, heart rate zones and photos - The Next Web
How to Connect the Scosche Rhythm+ Heart Rate Monitor to the RunKeeper App
Koen Delvaux's blog: Heartrate monitors and GPS for running: the Runkeeper-Magellan Echo dream combination that would beat Polar, Garmin, Tomtom and Suunto