What are some alternatives?
When comparing Effitask and Todoist, you can also consider the following products
Markor - Text editor - Notes, ToDo & Bookmarks. Markdown and todo.txt support.
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.
todotxt.net - A minimalist, keyboard-driven Windows GUI for your todo.txt file
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.
Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.
Remember The Milk - Remember The Milk is a task and time management application for mobile devices.