In an attempt to be able to create a rich application using ROR3 Jquery Mobile and phonegap after reading this article - http://fuelyourcoding.com/getting-started-with-jquery-mobile-rails-3/
I was wondering if it would be possible to render all of the apps content on the server side while jquery mobile handled all of the nice transitions?
Would the work as a phonegap app? (considering that no JSON is being used at all)
Yes, you can use ROR with jQM, no problem there. jQM will be used only to handle a HTML GUI restyling. But you are not going to have transitions with an ajax turned off.
Then again this should not worry you because transitions don't work well with the older Android platform's. Even versions 4+ have a few problems.
And yes, this app will work with phonegap, as I said previously just without transitions.
EDIT :
If you still want to use ajax (it can be done) you will only have a problem with form submitting.