A:AnswerI think it’s mostly the readiness score and perhaps more advanced reporting. The premium also comes with guided workouts, articles, and mental wellness / mindfulness cirricula.
A:AnswerNo the Inspire 2 only comes with the wrist band. A clip on can be purchased separately. Unknown if Best Buy offers it though. The clip counts the steps but without contact to your wrist the heart rate will not register.
A:AnswerYou could replace the battery if you are adept at using a soldering iron. However you would probably run the risk of voiding any warranty and potentially damaging the Fitbit in the process. These batteries generally have a long life span.