GYM One is described as 'Open-source, free gym management software designed to optimize the operations of fitness centers, personal trainers, and sports clubs' and is an app in the development category. There are more than 10 alternatives to GYM One for a variety of platforms, including Web-based, iPhone, Android, SaaS and iPad apps. The best GYM One alternative is TeamUp. It's not free, so if you're looking for a free alternative, you could try Fitune or Wellyx. Other great apps like GYM One are Easy Gym Software, appointman, StudioYou and EzeGym Software.