A Straight Talk smart phone using 3G Verizon is a good choice for what a lot of RVers consider the best overall coverage. But be SURE you buy the Verizon version of their phones. Straight Talk is also available for connecting to sprint towers - which you don't want. Straight Talk does not allow tethering (using your phone as a wi-fi hot spot). And in fact since they only allow 2.5 gig of service a month that would pretty much make tethering not too useful anyway. This a monthly pay as you go service.