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 here(itunes.apple.com)
IPAD here(itunes.apple.com)
I use GoTasks (free) to manage and sync my Google task lists across all my devices. And it obviously lets you also manage them in a web interface from your laptop or desktop via Gmail.
Not sure why this is so much better or why it would be worth almost $10 or $20 normally.