I recently did a set of Videos for the Scosche Rhythm+ Armband Heart Rate Monitor so users can visually see how to connect the Rhythm+ to 5 of the best Fitness Apps. Each app will connect to the Rhythm+ through the Bluetooth Smart Connection. Users can follow the instructions on the videos and see how to connect to their favorite apps as well as try new apps to exercise with.
One thing I find interesting is the different data sets and use cases for each app. Strava is very GPS Centric, while digifit iCardio is very Heart Rate Training focused. Endomondo is more about total Calories burned for gym goers with less emphasis on GPS centric data, while Runkeeper is a go to for outdoor Runners. Wahoo Fitness is an excellent app for the Scosche Rhythm+ which is FREE and no premium upgrades are required to get going right away.
I recommend giving them all a try and depending on what your goals are you will find which app naturally fits your use case. Check them out!