[Toadling]

Unfortunately, no. As of today, there is no way to trial OmniFocus for iPhone without actually buying it.

However, Apple recently enabled in-app purchasing for free apps in the iTunes App Store. What this means is that developers now have the option to offer a free version of their app with limited functionality, along with a built-in mechanism for later upgrading to the full version, all done from within the app itself.

I don't know if the Omni Groups plans to go this route, but I suspect we'll start seeing more and more apps on the iTunes Store using this model in the coming months.

-Dennis