First off, I apologise this maybe a little technical. The reason for this is incase anyone has any bright ideas, or can spot anything I've missed.
Second, sorry I didn't get a chance to sort out any testing or real code this morning or afternoon. I ended up running errands and spending some time with the girlfriend. However, I've had a quick 45 minutes play this evening.
So far;
* The Content-Type (multipart/mixed or multipart/x-mixed-replace) is a failure on anything running Internet Explorer 6, (or IE Mobile [including the one bundled with Windows Mobile 5]). Which sucks, as I was hoping that would work.
* IE Mobile does support XMLHttpRequest calls. (woo-hoo).
* IE Mobile does support meta-refreshes.
* According to a very, very quick google, the PSP does not support XMLHttpRequest (boo). The DS Lite browser (opera) also does not support XMLHttpRequest (boo).
So where does that leave things? Unfortunately at the meta-refresh option. Now the issue with that is that its got additional overheads of creating a request each time (like XMLHttpRequest), which is why I wanted to avoid using it. Although the bonus is that keep-alive is handy to avoid sockets having to be created and destroyed. Not exactly what I was hoping for though..
The other big issue with meta-refreshes, is that they aren't "pushing" data to the device, and instead will constantly barrage the OutGauge application. In itself this isn't a big problem (given todays average processing power), but the real killer is that the fastest this can happen is every 1 second (a limitation of the meta refresh "design").
Now this 1 second limit is potentially avoided by using a generic javascript option instead - which I'll have a poke around at tomorrow.
Sadly things aren't looking as rosy as I'd hoped for the web-browser idea, and bang goes the idea of using a one stop solution for all the various handheld devices