Nozbe is a clean, aesthetic task manager for the web, designed to make GTD as simple and intuitive as possible. It has a mobile optimized web-based application for any mobile device, downloadable iPhone, iPad, and Android apps to keep you connected everywhere, and features basic task-sharing for teams. Nozbe also has a desktop application for Mac and PC which syncs Nozbe tasks offline.
Nozbe Classic is a good option for people with a low-to-moderate task load (up to 200 tasks), more than one computer, or an Android, iPhone, iPad, or other mobile device. We recommend Nozbe Classic (this training tool) over Nozbe 3.5+ because Nozbe 3.5 requires more clicks to get to the views you need to manage your day.
Nozbe is also a good choice for people who insist on a simple, aesthetic interface. Nozbe also allows you to attach images to tasks. Nozbe’s collaboration features work well in a highly project-oriented environment, but are less effective for lone tasks because it requires you to create some kind of project and invite the person to that project before you can assign tasks to them (inside that project).
While Nozbe does have a free version, you will need to upgrade to the paid version, because you’re going to need unlimited contexts.