Pomodoro is a method to help you focus on your work in timed bursts and not make you feel guilty for taking breaks - http://pomodorotechnique.com/get-started/.

Perhaps you're thinking of GTD (Getting Things Done), a highly structured productivity/organization system that can be carried out with anything from paper folders to powerful apps? If so, Moo.do would work well since it supports using @tags for contexts, among other parts of GTD.