I have an Entry which uses the default Keyboard property, so when the user selects it the keyboard slides up and shows letters, with the option for the user to switch to numbers pressing the "123" button.
I'd like the keyboard to automatically appear in that mode rather than requiring the user to press the 123 keys as the most common values are numerical. Note that I'm not asking how to have the keyboard show only numbers, as the user needs to be able to enter in letters at times as well - it's just numbers are more common. I already know about Keyboard.Numeric, but this doesn't allow the user to also enter letters.
A similar discussion in the context of Android-only UI can be found here: http://forums.xamarin.com/discussion/11817/set-alphanumeric-keyboard-to-show-numeric-first-in-edittext-c-android