[mrspeaker]

The problem is making the distinction between "mobile site" and "mobile app". A back button for a "mobile site" should (arguably) act like the back button of the browser - especially for devices that actually HAVE a physical back button. But "mobile apps" should act like native apps (arguably) providing breadcrumbing (is that a verb?).

It's a tough choice and a touch coding experience too (have you tried using the history api to cover the case where the user presses the FORWARD button?! ergh!).

[daleharvey]

I think its best for both app developers and web developers and more importantly users if they settled on a single set of idioms, the web is an application platform.