I tried to place an iframe (display:block; width: 100%; height: 100%) inside a tab of a TabPanel (say this tab id = "promo"). The page loaded inside the iframe contains a div with -overflow-y: auto to enable scrolling on that div, and -webkit-overflow-scroll: touch to enable native scrolling.

It works, but when you switch to another tab of the TabPanel (imagine a classical "More" tab), and that tab contains a NestedList, some elements aren't clickable (unless you reorient the device).

I fixed this by listening on activeitemchange event of the tabPanel, to detect when user is leaving the tab "promo", containing the iframe, and applied this code to force a redraw (completely solves the issue):

	xtype: 'tabpanel',
	config: {
		listeners: {
			activeitemchange: function(source, value, oldValue, eOpts) {
				if(oldValue.id == 'promo') {
					setTimeout(function() {
					}, 400);