Best Practices for ASP.net App on Mobile Devices
In general the recommendations would be around how to develop for applications that would be consumed by mobile devices.
Build a Better Mobile Browsing Experience https://msdn.microsoft.com/en-us/magazine/hh288079.aspx
ASP.NET Web Sites for Mobile Devices https://msdn.microsoft.com/en-us/library/ms178619
Moreover you can focus on Responsive Design: Search for “Adaptive Layout” or “fluid layout”. For example, https://coding.smashingmagazine.com/2009/06/09/smart-fixes-for-fluid-layouts
It is about designing UI that will render on all type of devices
More Online articles:
https://www.alistapart.com/articles/responsive-web-design/
https://designmodo.com/responsive-design-examples
And for your last addition about SSL and Authentication method. That’s going to be an implementation detail. The Blackberry browser should support SSL and for Windows Authentication that depends. Forexample blackberry Support indicates that the browser doesn’t support integrated Windows Authentication.