I did make a simple test .
Test conditions :
VS2017 version 15.4.1
Windows 10 Fall creator
I started a new Xamarin.forms, cross platform, blank solution, Shared Library (not a PCL).
I updated the nuget packages, without pre-release.
I compiled and tested the Uwp et android projects, all was good.
After, I added a simple .net standard (1.4) library into my solution, renamed this default 'class1' file et class name, and added a simple static fonction :
public static bool True()
Very simple function.
I called the True() finction from the MainPage contructor into the shared project.
I added the reference of this new library into the project UWP and Android.
Compilation OK in both cases.
When I started the UWP project, no problem.
When I started the Android project with Xamarin Live player, I have some exceptions :
The type or namespace name '[My .net Standard library name]' could not be found (are you missing a using directive or an assembly reference?)
C:\Projets\XamarinNetStandard\XamarinNetStandard\XamarinNetStandard\MainPage.xaml.cs(1,1): error: The name '[My class name]' does not exist in the current context
What do I miss ?