Sencha Touch
There is a terrific mobile development environment utilizing Javascript/HTML5/CSS3 called Sencha. I have created a couple of apps using this framework and it really eases the development time.
I am still tinkering with the platform and Sencha announced yesterday the release of Sencha Touch 2.0 PR4.
Today, they also announced Sencha Labs…
In the mean time, here is a resource for digging in to the capabilities of Sencha touch.