Typically, Best Buy has three stages for their interview process, screening over the phone, in-store supervisor or manager interview, and a final interview with the general manager of the store.
Easy questions like "what would you do if a coworker was stealing from the company?". Managers were very nice and easy to talk to. Overall good experience and simple for a college student to apply.
I would say that knowing how mobile phones tie into daily life will help you frame your mind for the interview. Also good to know the different ways phone plans work.