Hello,
I'm getting errors which i don't know if are bugs or just my dumbness 
I create a new project (shared or portable, gets the same result). Try to add Xamarin.Forms.Maps to all projects, and get this error:
Could not install package 'Xamarin.Android.Support.v7.AppCompat 21.0.3.0'. You are trying to install this package into a project that targets 'MonoAndroid,Version=v2.3', but the package does not contain any assembly references or content files that are compatible with that framework. For more information, contact the package author.
I searched this issue and was told that i should change the "compile using Android version" to a specific one, which i did - API Level 11 (Xamarin.Android v5.0 Support). This solved the problem. But then, i tried to test the app - the blank app, just with the Maps package installed, not even changed one line of code - and i get:
No resource found that matches the given name (at 'value' with value '@integer/google_play_services_version')
I unloaded and reloaded the project, and now, it just won't run on Android. It doesn't even give me an error, just starts building and then it is like i ended the process again.
What am i doing wrong? I've been trying for days to using Maps and i just can't get it working. I downloaded the sample and I get an error saying i got to download and extract android_m2repository_r15.zip, which i did. And then i get bunch of "XXXXX does not contain a definition for YYYYYY".
Thank you for your attention