A:AnswerBoth, but the easiest way to keep her expenses would be to buy a prepaid phone and the sim card from AT&T has good reviews and little interruptions as well as unlimited data plans, and you can provide a credit card and set it in a way she does not have to worry about running out and being auto renew
My advise
AT&T and go prepaid
Good luck
A:AnswerYes it does need a sim(sd card is something totally different). A Kronos Blade Genesis isn't a normal smartwatch...it has full blown Android 10. It can receive notifications but cannot respond to texts or make phone calls when linked to a smartphone