Elliot's aunt is visiting and wants to know who would be the best carrier to get her smartphone from in St. Louis? Leo says that his experience in the Midwest is that Sprint is really good. That's because Sprint was spun off the Southern Pacific railroad. But they can't go wrong with AT&T and Verizon. The best way to find out is to go to OpenSignal.com, enter the zip code, and they'll see who's got the best coverage in the area.