SimplePractice - With SimplePractice, manage your notes, scheduling, and billing all in one place. Conduct secure video appointments with Telehealth by SimplePractice.

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

TheraNest - Mental health software for psychologists, social workers, therapists, counselors.

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

drchrono - An EHR built for your specialty:

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.