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.
appointman - Online booking solution for gyms and studios
Task Coach - Task Coach is a simple open source todo manager to keep track of personal tasks and todo lists.
Bookamat - Powering the world's best independent fitness, Pilates and yoga studios.
Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.
Presence AI - Presence AI enables your customers to BOOK business services by TEXT MESSAGE over your landline. AI-powered appointment booking, confirmations, & more.