-Tested with the Garmin ANT+ HRM strap and Endomondo sports tracker app.
Set up was quite easy:
1. Connect USB2 stick with USB OTG cable
2. Open Endomondo, ->Settings -> Accessory Settings -> ANT+ Sensors
3. Follow prompts to install three ANT+ Services from Play Store (ANT Radio Service, ANT USB Service, ANT+ Plugins)
4. Put HRM on - it seems like it will only turn on and connect when it is broadcasting your heart rate
- Garmin USB stick must be version 2 (labelled USB2) for it to work
- I took a quick look in the Runtasic app settings and I don't see anything indicating support for ANT+ sensors
- I have don't have any other sensors to test (pedometer, cycling speed, cadence, etc)
- Moto X is running Android 4.4.2 Rogers/Fido release, not rooted.