Finding more and more users that are unhappy with iPads in the field. Operation in sunlight is the main complaint. Since we already have iOS and windows devices supported there is angst about supporting an additional operating system like Android. We'd rather limit it to two. That said, the limits we face if we use Windows tablets in the field are significant. I find it odd that despite a strong relationship to between esri and Microsoft, that applications such as Collector are not supported on Windows tablets.
Hoping this will change soon!