Simpletasks Dropbox vs 2Do

Just like todo.txt cli, this is 100% free (although donations are accepted).

For those who don't care about syncing there is a cloudless version while people who run Owncloud may opt for the Owncloud version.

This not only tells one's calendar (and thus any devices that sync with your calendar) about the todo, but allows all synced calendars to play an audible alarm when the todo is scheduled to be finished.

Let's one sort to-dos by due date then priority

2Do conforms to your workflow instead of forcing you to conforming into some preset workflow. It helps to accommodate your workflow through a series of features including tags, batch editing, configurable presets, and the ability to quickly add tasks at any time.

Adding a task can be as simple or complicated as you like. A to-do list entry can simply consist of its title, or you can also add notes, recurrence, set a due date, tag a location, schedule an alarm, priority (low, medium, high, starred) and tack on a URL or photo. You can even make an audio recording with voice notes. And each list is sortable by a number of criteria, including priority and due date.

Unlike many other apps that will release a new paid version when major features get launched, 2Do doesn't resort to that.

Use a combination of tasks, projects and checklists.

You can use 2Do according to the Get Things Done methodology – or not.

Find old tasks or organize smart lists based on complex search terms (for example, “tasks to do at home between 6 pm and 11 pm”).

The app can optionally sync with iCal or Outlook with free helper software available from the 2Do Website.