I don't believe that, iPhone 6s was probably the most popular smartphone in 2015, but 2016 belongs to S7 Edge
My prediction: the Galaxy S7 Edge it's the best selling smartphone in 2016, it should be! unless Samsung it's having supply problems keeping up with the demand? If is true? that's bad! because its Samsung...that means will be a problem for Apple too! next year with the iPhone 8