[Callers] which device works best

I am interested in having recorded music to take with me to a class or possibly even a dance where there are no musicians.  If I were to load music and callers companion onto a device which one(s) would be good to consider? Maybe I would only be able to load one or the other. I have taken my laptop for music to play through a speaker.  I have never used callers companion and would like to try that. Suggestions? ThanksPat Reeser