Re: Nuance
"Windows Phone's tiny market share is the major reason for its security record.
(Pretty certain you've mention this about Linux)"
Linux has historically had both a small market share AND a terrible security record.
Don't just take my word for it - how about some people that look at phone security for a living:
http://betanews.com/2015/06/11/windows-phone-security-is-top-notch-says-kaspersky/
http://www.neowin.net/news/microsoft-may-have-the-most-secure-smartphone-os-in-windows-phone
http://www.v3.co.uk/v3-uk/news/2222370/windows-phone-safest-mobile-platform-but-android-security-epidemic-spreads