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.

eClinicalWorks - eClinicalWorks - the largest Cloud EHR in the nation. Make the switch to eClinicalWorks

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

Kareo - Kareo - Go Practice | Medical Office Software for Small Practices

Task Coach - Task Coach is a simple open source todo manager to keep track of personal tasks and todo lists.

WebPT - WebPT is a completely legit and reliable physical therapy automation software platform that allows rehabilitation centers to streamline their business operations.