Things is one of the best GTD (Getting Things Done) applications. It is a delightful task manager that's easy to use, yet has all the power when you need it. Projects, tags, repeating tasks - all at your fingertips. And no matter what device you're on, Things Cloud keeps your to-dos updated across them all - automatically.
iPhone Version(itunes.apple.com)
iPad Version(itunes.apple.com)
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