I use Verizon and have never had a problem at any of the parks, Downtown Disney or at the Contemporary, Polynesian, Wilderness Lodge, Grosvenor, Wyndham Palace or Hotel Royal Plaza. I can't say it works everywhere because I haven't been everywhere but I have never had a problem at any of these places. Also never had any problems on buses, boats or the monorail either. I also know it worked on Alien Encounter, the railroad and the tomorrowland speedway. LOL