I currently use adobe air to help create desktop applications at work. This program comes in handy when trying to make them crossplatform compatible.

With a single code base I build complex applications for iOS, Android, Window and PC. My apps run great at native speed. I have several in all the different app stores. And whats great is, as soon as a new device or app store becomes available, Adobe Air will be quick to create publish options for that too, allowing me to use the same code for past projects to be the first to the new platforms. Also, Airs drawing and vector capabilities can't be beat, for all the different screen resolutions this is a game changer. Actionscript is an awesome object oriented language.

- Targeting iOS, Android, PC and Mac OS X with the same code base, with ANEs to target platform specific functionality as required. There are off the shelf ANEs for almost anything, but you can write your own (or get someone like me to do so) if there's something else you really need. - Choice of IDE. I use FlashDevelop (which is free, and fantastic) and do everything in code, you can go the Adobe route with Animate CC if you want a graphical IDE. - Being able to do nearly everything from a PC, including building for iOS. For example, you can build and debug directly on an iOS device - yes, debugging on an iPhone from a PC. You still need a Mac to build for OS X, and for submitting to the app store. I use Xamarin as well and in comparison the build process for iOS is a long slow joke. - Performance is excellent - you have to write decent code of course! You can run multiple threads, although the implementation is a little awkward at first. - Regular updates of the AIR runtime.