Ubuntu Touch SDK is obviously in an early stage, but the works on Apps for it have already been quite active. And so, multiConvert is currently on the stage of porting to Ubuntu :)
Up till now (March 30), the Go mobile section of Ubuntu App Developer site indicates that it is our choice to develop apps for Ubuntu natively or using HTML5, but at the same time leaves us unclear about how to deploy HTML5 app in Ubuntu. But hey, to simply make it run, it is easy! :D