HTML5 apps on all platforms: can Qt help?

A couple of questions for my dear Qt friends: after a long winter, mostly devoted to building and deploying HTML5 games and educational apps, I find myself evaluating Qt again for a big project… It is an app to be used on schools: it must work online and partly offline as well. And it has to run on desktops (Linux/Win) and mobile (Android/iOS).

HTML5 apps have evolved a lot. We built very interesting collaborative things using it, and the team is already familiar with backbone.js and other goodies. But the requirement that part of the funcionality must be available offline is puzzling me for this particular project. HTML5 offline support will not cut it, as data to enable the features we need is not something that fits in the typical localstorage cache solution. So I was thinking about using something like Apache Cordova (previously phonegap) and its sqlite plugin. The thing is that I would very much wanted a single code base…

The research lead to interesting new projects, like node-webkit and chromium embedding framework. All have pros and cons, and none runs on all platforms we need to support.

And then yesterday I found that ICS was working on cordova-qt. So maybe it is possible to build such an app (HTML5 based with local fs support) and really deploy it worldwide from a single codebase? Apparently, not yet… the project appears to be a bit stale. Does anyone know why? Perhaps the announcement that Digia will work on native iOS and Android versions of Qt has made this a lower priority? It would be nice to use a C++ app with QtWebKit, but IIUIC this does not work for iOS and Android, so back to square one, right? Comments are welcome!