This document discusses various options for building mobile enterprise applications, including developing native applications, using HTML5, PhoneGap, Xamarin, and the Citrix Mobile SDK. It provides pros and cons of each approach and examples of how they work. Developing truly native applications may be best but is also most difficult, while tools like PhoneGap, Xamarin, and the Citrix SDK allow developing cross-platform applications by wrapping or compiling to native code but have limitations compared to native development. Detection of mobile devices connecting remotely is also discussed.