5GB data plan: $15/month @ T-Mobile The cheapest plan from the three major carriers can be found at T-Mobile, where you'll pay $15/month for the same 5GB AT&T charges twice as much for.

(Bloomberg) -- Walmart Inc. is expanding its offerings of prepaid phone plans with MobileX, a wireless service launched earlier this year by Boost cofounder Peter Adderton. Walmart will be MobileX ...