http://www.techradar.com/news/the-best-bluetooth-headsets

The best Bluetooth headsets make hands-free calls simple, whether you’re trying to do ten things at once, broke both of your hands trying to answer your phone the normal way, or just jogging (though we have some other recommendations for the best headphones for running). 

As good as our smartphones can get, sometimes it’s just not convenient to pull them out of our pockets and mash them against our ears for what may be hours at a time, and Bluetooth headsets solve that problem.