Meistertask VS EssentialPIM

Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.

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

Asana - Asana project management is an effort to re-imagine how we work together, through modern productivity software. Fast and versatile, Asana helps individuals and groups get more done.

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

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

Strikethru - Strikethru is a kind of to-do list notebook for managing work lists and staying updated with the important tasks.