GMail and other web applications have adopted a new technique coined Ajax (by Adaptive Path). It brings web applications a step away from the stateless web and closer to real applications. It’s harder to built applications with the applications, but it’s hot – and the most recent release of Rails (for Ruby) promises to make it much easier to do Ajax applications. Before you do too many Ajax applications, do think for a second. Tadalist is a great example which could have been so much better with less Ajax code. The application rocks in a browser – if you’re at a full computer where the browser knows about and fulfil the requirements posed by the Ajax technique.
While it would be a nice – maybe even cool feature to be able to check my todo-lists and add items on the road I can’t. And the reason isn’t the design requirements (which are usually the most common case). Most of the design is quite usable on the P900 – it’s the Ajax it doesn’t like.
If you have a cool simple application – or features which may be of interest to mobile browsers, PDA users or others without a computer – don’t spoil it with fancy techniques – or do offer some graceful downgrades for non-Ajax users.