OmniOutliner for iPad v1.5 is a major update that adds automatic document syncing through OmniPresence. (This release requires iOS 6.) This app is an outlining app like no other for your iPad. If you have a need to outline thoughts, ideas, arguments, papers, notes and more, you should look at this app.
With this update, OmniGroup introduces OmniPresence that is designed to work with any Mac app that supports OS X’s auto save and versions. According to the developer “OmniPresence lets your app know when a document has been changed on another device, and double-checks to make sure it always syncs a current and complete copy of any documents currently being edited. OmniPresence can’t prevent conflicting edits from multiple devices—but when that happens it automatically saves both versions of conflicting edits so that no edits are lost.”
You can learn more about the app at the OmniGroup’s page that explains OmniOutliner for iPad.