I'm really sorry for the trouble! We'd like to take a look at your iPhone's crash reports. Can you do me a favor and sync your iPhone with iTunes, then look for files with "OmniFocus" in their name in any of the folders inside this one on your computer?
<your home folder>/Library/Logs/Crash Reporter/MobileDevice
If you can send along any crash reports you find to
omnifocus-iphone@omnigroup.com, we may be able to determine what's happening and fix the problem. Thanks for your help!