Ask HN: Cross-platform mobile app development

With the announcement of the Visual Studio Community Edition and Android Emulator, I think many of us who currently build iOS and Android versions of their apps in completely separate code-bases (Objective-C & Java) would be interested in learning from the experiences of those of you who have tried to write cross-platform native apps for iOS & Android or share most of the application logic between the two versions using Xamarian or good-old C++ (or anything else).

- How was your experience? What about debugging, maintenance, performance, etc?

- Is your app somewhat complicated (for example, it uses custom UI controls, animations, etc)?

- And finally, if you have to build a complicated and actively developed app on both iOS and Android now, what platform would you use (assuming your level of familiarity with all of them is equal)?

I've read time and time again that non-native cross-platform solutions like PhoneGap etc still don't give a smooth enough experience to compete with native counterparts. So, I'm still not taking them seriously.