For example, open the Sencha Touch O'Reilly example either in the Android web browser, and drag the bottom tab-bar to the left before the first card has finished loading (while the spinner is still showing); it will move the whole viewport and leave a very obvious white gap on the top toolbar and on the right of the fifth tab-bar icon. It is possible to drag the whole viewport back again but only when something is still trying to load. I get this problem quite often in standard use.

I have tried <body style="overflow: hidden"> and <meta name="viewport" content="width=320; user-scalable=no" /> but the problem still happens.

This is only on Android, not iPhone.