[Stargazer]

I use OF on iPad without desktop (though I did later get it on iPhone as well. The iPad version of OF is fully functional, and I think many folks consider it to be easier to use than the desktop version. That said, it is an iPad app, meaning that you'll have to be comfortable typing on the iPad and viewing things through the iPad interface to use it. But then that's true of all iPad apps. You certainly do not need to have a desktop version of OF to use the iPad version.

I checked a few other iPad alternatives like Appigo's ToDo and Toodledo and Things, but ultimately rejected them because I wanted the features that OF offered (sync, subtasks, folders, etc.).

My only caveat would be that I find the usefulness of OF to be much greater when I can view my information on my iPhone as well as iPad, because I always have my iPhone with me. With both sync'd together, I can use the iPhone as an all-the-time capture device, as well as being able to use it for errands, grocery lists, and so on without having to lug the iPad everywhere.

If you have a mobile device but not an iPhone, then it might be worth it to find a solution that lets you sync to that mobile device as well.

One other thought -- the main knock most people have against Things is that it doesn't really have a workable sync solution. If you aren't going to sync anyway, then Things might be a workable alternative as well.

But to answer your original question, yes, OF on iPad is worth the money, and no, it isn't necessary to have a desktop to sync it with.