This belt works well, then we can simply wonder about the usefulness of having a cardiovascular centure but not be able to display real-time its heartbeat Runtastic will simply cut your music every 30 seconds to tell you "heart zone 5" or "Heart Zone 6", short particularly painful especially if you oscillate between 2 zones Unless a very good configuration runtastic so you'll quickly start running without the belt
Otherwise a functionally no complaints for the price the service is rendered and it is the main