I use the Sport Plus chest for some time now with my Samsung Galaxy S4 mini + Runtastic and am still confident. The device as Runtastic device is easy. (It does not have to search for Bluetooth devices - that I had done wrong in the beginning Runtastic place the belt by itself :)..)
It is helpful in any case the built-in NFC chip. I can so the runtastic app (or any other) can start automatically when I hold the belt in the vicinity of cell phones. For this I use the app "Trigger". The display of pulse rate by a built-in LED is well resolved. So I can see at a glance that the belt a) work has b) connection to the mobile phone and c) still has enough charge the battery.
The water tightness can I confirm that I have already washed the belt and he still runs. As a special feature, I feel the removable transmitter. So the chest belt can be washed without electronics.
I'm excited about the specified battery power of 3.5 years. Should the battery to give up at some point, it's still not the end of the belt: it can easily be changed: A commercially available button battery is installed in a watertight compartment on the back and can always be replaced.
