The Omni Group has OmniFocus (iTunes Link) for the iPad in the iTunes App Store for $19.99 (39.99 – 50% off) and OmniFocus for the Mac in the Mac App Store for 39.99 (79.99 – 50% off) for a limited time.

OmniFocus is designed to quickly capture your thoughts and allow you to store, manage, and process them into actionable to-do items. Perfect for the Getting Things Done system, but flexible enough for any task management style, OmniFocus helps you work smarter by giving you powerful tools for staying on top of all the things you need to do.

OmniFocus for iPad combines the in-depth task management features of a desktop app with the advanced mobile experience of the iPad. With flexible viewing options, location-aware task lists, and on-the-fly task entry with voice notes and image attachments, OmniFocus for iPad is the trusted system you need for managing everything in your busy life.

Use OmniFocus for the iPad or the Mac on its own, or sync through the cloud with your other devices running OmniFocus.

The Omni Group also has OmniFocus (iTunes Link) for the iPhone and iPod Touch in the iTunes App Store for $19.99.