Using jQuery Mobile, an application with two pages. On the second page there is an IFrame element with no source (src=""). jQuery Mobile's OnPageBeforeShow event is used to set the src property to a website (tested with OSM and example.com) like this:
The page is successfully loaded inside the iframe.
When you go back then, either with the Back button of the Android device or with the navigator.app.backHistory() method, the content of the IFrame dissapears. If you hit Back again (any of the methods also), then it works as expected.
Seems the load of the iframe is counted as a third page on the application.
The thing is, on the mobile device I used it works as expected (as I expect at least), hitting back takes you to the previous page directly.