Windows Mobile app with a very usable interface. Integration with email, you can manage email, projects, tasks, appointments, contexts. Task delegation and email-to-task conversion are supported.
A video demo (less than 3 minutes) can be found in youtube:
http://www.youtube.com/watch?v=qAMbEU0OWgg
It covers all the stages of GTD: http://www.needian.com/time-management.php http://www.needian.com Home/GTD-Software/
