Not surprisingly, BlackBerry 7.0 gained the highest average score (2.89) across a vide range of factors including built-in security, application security, authentication, device wipe, device firewall, and virtualisation. Although BlackBerry offers corporate-grade security and manageability, many of its advantages can be lost if devices are user-provisioned via BlackBerry Internet Services instead of being managed through BlackBerry Internet Server.
Apple's iOS 5 was a distant second (1.7), followed by Windows Phone 7.5 (1.61) and Android 2.3 (1.37).
The key advantages of iOS were said to be the application sandboxing, the absence of removable storage, and (in the BYOD context) the way an IT department can only configure items after the user has granted permission.
Similarly, the report notes Windows Phone's sandboxing with control over access to system features by applications, and that unsigned applications will not be run. In addition, where the hardware manufacturer makes provision for removable storage, the media is locked using a 128-bit key that ties it to the original phone.
What about Android? Please read on.