The iPhone's browser renders the "real Internet" (after sucking the data through a pipette, and assuming your Internet doesn't include Flash applications). But notwithstanding the iPhone, it's a safe bet that making your application or data accessible to phones will involve publishing some kind limited type of html, xhtml, chtml, wml, etc. Probably all of them, using an adaptive rendering mechanism.
This page composer loads slowly and doesn't impress at first glance. But wait … keep going… it’s got templates ... AJAX editing ... limited forms support … an image resizer … a page hit counter … 1-click SEO-er-izer ... and automagic versioning with the ability to easily rollback to an earlier version.
In addition, there's a "wizard” that lets you add useful pseudo-widgets to mobile pages with one click -- things like launching a phone call from the browser, getting driving directions, viewing audio/video clips, even making payments via bango.
Then it generates slick reports (by ready.mobi) on how compliant the resultant site is, including running it in multiple emulators right in the online report.
Finally, there’s an integrated publishing workflow, where you can check your work and publish to your own site, publish to a free site provided (yourname.websiteforever.mobi – which is prolly a bit much to type on a phone!), or download your files. For complex sites with any kind of application functionality, you'd probably have to employ this last function and add use that output as template material for your ASP.net, PHP, etc.
If you are too lazy to press any buttons, there’s a demo movie.
Sprint and mobiSiteGalore call this “the world's first standards compliant mobile website design tool” with a “Guaranteed test score of 5/5 on MobiReady Report” that is based on w3c standards.
Which is nice. Now if only the mobile phone browsers were standards compliant too …