Todotxt+ for iPhone: Plain Text Task Manager
Plenty of successful people rely on to-do lists to manage their daily tasks. The Todotxt+ for iPhone is an awesome app that lets you easily manage your lists on your smartphone. It is a Plain Text task manager that lets you add, prioritize, and categorize your tasks.
The app comes with an editor to create multiple tasks and filter them fast. Dropbox sync functionality is built-in. On your iPad, you can take advantage of split-screen view. You can search tasks on your home screen. The app is available as a free download but you can unlock all its features for $4.99