Hello,
I used forms at the end of last year and it's a good idea but many things still prof of concepts and remain unfinished. The next examples are from the end of last year so if I'm wrong, please tell me.
Maps => doesn't support simple things like polylines, ... so it's normal if nobody can use it. Please, add a descent set of commands / events and people will start using it.
OpenGLView => there is no event like click and the position of click. What can we do with ? I have done an array of unvisible buttons to do my job...
Please start thinking that if a control is not popular enough it's not because it's useless but it's because it's a way too limited. And it was reported on UserVoice but ignored for a long time. Always the same response, you can integrate it from a guy that did it on GitHub but it's always complicated and a waste of time.
To avoid misunderstandings, my remarks are positive. I love Xamarin but I was forced migrating to another tools (that are not perfect too) just because some basic stuffs were missing in forms... Please don't think to the next functionnalities but do a second pass on the actual ones (what is missing, how to get users spend less time, ...).