Cross domain requests - how it is not scalable for Mobile Web

Many times, you might want to download data from a service hosted on a different or a sub domain. The usual approach is you add a script tag in your DOM with src tag set to the request url. The request url in turn returns javascript that calls a javascript function on your client passing the data as an argument to that function.

However, this technique is not scalable for all mobile web browsers. I know for sure that this technique fails on HTC Incredible. I will tell you why in a moment. But to verify my claim, I went ahead and looked at Google mobile site. Google Mobile usually hosts its autosuggest service on a different domain (for many reasons - less load on their main production server, increasing maximum number of parallel connections etc.). Look at the server to which the browser makes request for an iPhone and HTC Incredible UA:

As you can see, Google clearly differentiates between these two phones in the way it make request for autosuggest, for iphone case - it uses cross domain request and for HTC incredible, it uses ajax to download the suggestions. What essentially happens in case of HTC incredible is browser gets in old state. If you keep making requests using the same script tag or creating new script tags or each request, the browser does not evaluate the script response from the server immediately. But if you give some sort of poke to browser (by either touching the screen or by invoking alert etc), it will invoke all the pending functions call immediately.

I wonder on how many other phones this behavior happens. I hope not a lot.

If you wonder how I produced these waterfall chats, by ofcourse faking the UA from my firefox browser. But may be in future, I can use steve souders bookmarklet to produce waterfall directly on mobile devices.