Doit.im - Doit.
Task Coach - Task Coach is a simple open source todo manager to keep track of personal tasks and todo lists.
The Hit List - Your life is complicated, but managing it doesnt need to be.
TickTick - TickTickis a cross-platform to-do list app & task manager helps you to get all things done and make life well organized.
TaskUnifier - TaskUnifier - Task Management Application
DoItRight - DoItRight is a simple to use task management application that comes with an elegant way to manage your day-to-day activities, and you will be able to increase your workflow in the meantime.