I've been developing a travel planning site - tripgrep.com - which is built on appengine, GWT and smartgwt, among other technologies. It is still early days, and the site is now working well on my development environment, which is either a windows or mac computer.
However, I am frequently talking up the website to my friends when we are at a bar or other venue, so I am standing there while they try to access the site via an iPhone, Android or Blackberry - I've witnessed all three. It has been painfully obvious that the browser based frontend takes a long time to download on a mobile device. I am pretty sure this is because of the javascript download for SmartGWT.
So, I would like to look at alternatives to SmartGWT.
What I like about SmartGWT is that it has a reasonable look and feel out of the box - I don't need to learn any design or css and it has an office application look. This is considerably better than the GWT built-in widgets, which just get a blue border. The better look-and-feel is why I went with SmartGWT early on. However, the slow load times are killing me on these mobile demos. So now I want a fast loading widget alternative that has good look-and-feel out of the box.
The features I care about are: tabs, good form layout, Google maps API integration, grid data viewing. If those are all available in a library that loads quickly on a mobile device, then that's the library I want.