Bookamat - Powering the world's best independent fitness, Pilates and yoga studios.

Todoist - Todoist is a to-do list that helps you get organized, at work and in life.

appointman - Online booking solution for gyms and studios

Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.

Glofox - Powerful Gym and Studio Management Software.

EssentialPIM - EssentialPIM is a free Personal Information Manager that keeps up with the times and lets you manage appointments, tasks, notes, contacts, password entries and email messages across multiple devices and cloud applications.