Find problem:Omnifocus 2 IPAD can't use webdav sync in IOS9

find problem:Omnifocus 2 IPAD can’t use webdav sync in IOS9,
use webdav in setting, omnifocus halted.

My apologies for the trouble! We are not currently supporting the beta OS versions, though we will be ready as soon as iOS 9 is ready for release, and will have compatible TestFlight builds available well before then.

Omni Apps on OS X El Capitan and iOS 9

If you need to revert to iOS 8, Apple has provided instructions in their Apple Beta Software Program FAQ, under How do I get a shipping version of iOS back on my iPhone, iPad, or iPod touch?

Please send an email to omnifocus-ios@omnigroup.com, so we can file a bug report; once we move to iOS 9 work, we’ll definitely prioritize the issue!

Thank you for reply,I can wait for IOS9 formal edition.

Wonderful to hear! If you run into any other issues, please let us know.