SAP UI5 - SAP.M Lib - Pinch to Zoom in Win 8 Tablet

Hi Experts,

I was exploring the sap.m library of SAP UI5. I built a sample application using the Fiori style (followed the docs on SDN). I have deployed this app on the HANA cloud web server. I am accessing this application on a windows 8 tablet. Everything works good, except that I cannot pinch to zoom. However, if I access other sites like say google.com, the tablet allows it. Why a different behavior for UI5 apps? To confirm there is nothing wrong in my app, I accessed demo UI5 apps on the SAP portal. Same behavior. Cannot pinch to zoom!

I tried accessing the same app on a android phone and surprisingly I am able to use 'pinch to zoom'.

Any comments on why this is happening on windows 8 tablets?

Thx.