Since latency is the bane of even the fastest 3G networks, having extra proxying in the path makes the actual go-to-page browsing way slower than usual for a mobile. On the other hand, you have that warm feeling that practically any page, even moderately AJAX-y ones, will actually render attractively and usably when they do show up. Contrast this to the Blackberry browser experience, where the data starts coming down very quickly, but the device spend 30 seconds thinking about how to render it, and then ultimately produces something barely usable. Since subsequent navigations seem to perform better than initial ones, I suspect the Opera server is chasing forward links and preparing them while you read the first page. Not a bad plan.
I started wondering: Would Opera Mini serve well as a "base platform" abstraction layer for mobile web apps? If I code to O.M., and I can expect to be able to run unmodified on handsets all over the world, there's significant value in that.
What are the costs of such an approach? Hmm... let's see...
- Like all abstraction layers (Win32/POSIX/.net/...), the end user has to get it up and running. Sounds easy, but ask anyone who's ever wanted to deploy a "lightweight" .net or Java app and assumed users would already have the runtime ready to go...
- Opera has a done a lot of heavy lifting, but what if they change their browser capabilities, and now there's another fragmented set of clients, just a layer up the stack?
- Like all abstraction layers, there's a performance hit. In this case it's twofold: the memory and CPU usage of the Java runtime hits some devices pretty hard, and the proxy-through-Opera network access is painful even on EV-DO
In the end I think I'll take the weaselly way out for now. I wouldn't go all in, build an app, and say to the user "Opera Mini is a pre-requisite for this app. If you get it, you're golden; if not, no support for you!" I'd target a base of browser set with some kind of adaptive rendering. But I might well make Opera Mini the first-tier tech support response for any native browser problems.