This is actually the hard part, and the failure at this point actually prevents us from moving towards with Xamarin.
We have been developing with native iOS and Android for 6 years, with lots of legacy code and libraries. Our libraries in both iOS and Android can have up to 20-30,000 lines of code. To migrate all of them to Xamarin would be a huge deal. The only solution is to connect Xamarin with those libraries.
We have libraries in 3 languages: Objective-C, Swift and Java. The first trouble came up when Xamarin could not connect with Swift framework. In our experiment, we took the risk and port 1 of our library into Objective-C. The Swift framework issue should have signaled us that something was not going right.
Anyways, we move forward with our intention to write a real project, working on both iOS and Android, and connect with 5 of our libraries and use 3 cocoapods frameworks/libraries.
For the libraries we wrote, there was not much problem, except the Swift issue mentioned above. However, with cocoapods, when people write code in all shapes and forms, the API definition kept having weird issues that we could not comprehend. We spent 3-4 man days on this, and still wasn’t sure that if the code would work or not.
We will discuss more about what binding issues we have with Xamarin that forced us to change the direction: to try to at least make a workable app with missing elements and libraries working in Xamarin