The reason I got it is to do Crossfit and not be hindered in my workout routine. Essentially, instead of buying a heart rate monitor, you buy a device that goes on your arm and is quite convenient! What concerns me, and I don't know well, is that I have to be in other apps to see the heart rate from my phone and not in its own, or rather I still don't know how to use it. I will do an update soon regarding both the apps and swimming