If you use GTD principles or just want the most impressive to-do app out there, this is it. Ive tried Toodledo and a host of others but 2Do combines a very rich feature list with superb ease of use. 2Do puts Things to complete shame.
What 2Do calls "Lists" are simply the different tabs for separating work tasks from home or school tasks; the tabs are brilliant and you can drag tasks from one tab to another.
When you create a task, it can be a to-do, or a project, or a checklist. Projects can have a series of to-dos under the project and each of these can have their own due dates. Checklists are tasks or items without a due date: good for shopping lists!
For syncing you can sync over the air to Dropbox, CalDAV or Toodledo.
Highly recommended for professionals who have a lot of work to manage. The developer also provides a desktop version for Mac users. The price is worth it. This is an app that makes task management better than any other Ive tried in the App Store.
W Macaulay about 2Do - Todo List, Tasks & Notes, v3.8.3