I took that bracelet to show my heartbeat in Runtastic application (ANT +) on my phone Sony Xperia Pro in my sport (I can not put a chest belt). Although he works bluetooth 4.0, this is one of the few bracelets that also works with ANT + technology compatible with some Android phones Other bracelets often operate only in Bluetooth 4.0 for Android> 4.3 or latest iPhone. Attention for Mio Fuse operates autonomously, it must be loaded once and the first set with a Bluetooth phone with the 4.0 million Go application (rate zones, time, fashion righty / lefty , ...). It looks to be mandatory. I made this configuration Mio Go from an Android phone 4.4 does not belong to me because my Sony Xperia Pro Android 4.0 and Bluetooth 2.1 ... I then downloaded the ANT + plugins on Google Play and ANT + enabled on my Sony Xperia Pro. In sports, I support the middle of the watch (it is necessary that the arm is horizontal to the touch screen of the watch is active) for 2 seconds. FIND is displayed and my pulse is found within seconds. Then I run Runtastic on the phone and I connect the watch in the settings. Then it's party (press left or right of the screen strap, arms horizontally, to change the display, Distance, Time, Calories ...). It vibrates when changing frequency bearing (Mio defined in GB) and the display of rhythm appears (the display is off but can be activated by continuous attention to ... the battery). In parallel, it is also possible to launch an activity once the bracelet cardio activated by pressing a second time on the middle of the bracelet (not hold down). To stop, push a few seconds in the middle and the activity stops (a short press corresponds to Pause). This operating mode is also available for stand-alone mode. The bracelet can also work without the cardio 24/24 on (to save power) in standalone Step mode (obviously not be counted against the arm of the balance and not in relation to vibration during no). The autonomous activities with or without cardio can be synchronized activated every x days on a Bluetooth phone in 4.0 million GB. This is a good bracelet. It is waterproof (swimming). It apparently can evolve (firmware). Like the Mio Go application in its infancy (ANT + mode synchronization and Android compatibility There is no sleep analysis mode as some bracelets autonomous and self-Step mode might be be improved. Continued on time ...