I follow a slight variant of GTD, and use my Todo.txt for Android app for task list management. Here are two tweaks I use in the app for parts of the GTD process—quick capture, and easy identification of next actions.
1: Use a special project for quick ‘capture‘
I use ‘+quicktask‘ as default project for all new tasks to quickly capture them. This allows me to just note the task in plain English and continue with the task at hand. I don’t need to think about their priority, due date and all other things at the time of capture.
Writing the task down closes the loop and frees the mind. Applying the +quicktask project allows me to easily find the task later during the clarification stage.
When I’m in the clarify or organise stage, I filter the task list for +quicktask and process them.
2: Use a special tag to mark the ‘next action‘
I use ‘#next‘ tag to indicate the next task to focus on in a project. During the organise stage, I mark one task in each active project as #next. This ensures that I don’t have to look through the task list for what to focus on next.
My task list widget is now filtered by #next and sorted by due date. What’s on top, is what I need to focus on now.