LoginPage.xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="App1.LoginPage">
  <ContentPage.Content>
    <StackLayout Orientation="Vertical" Spacing="8">
      <ContentView Padding="16, 16, 16, 16" BackgroundColor="Gray">
        <Label BackgroundColor="Aqua"
               Text="Very long text in single line to be truncated at tail.  Adding extra text to make sure it gets truncated."
               LineBreakMode="TailTruncation" />
      </ContentView>
      <ContentView Padding="16, 16, 16, 16" BackgroundColor="Gray">
        <RelativeLayout BackgroundColor="Navy">
          <Label BackgroundColor="Blue"
                 RelativeLayout.XConstraint="{ConstraintExpression Type=Constant, Constant=0}"
                 Text="Very long text in single line to be truncated at tail.  Adding extra text to make sure it gets truncated."
                 LineBreakMode="TailTruncation" />
          <Label BackgroundColor="Fuchsia"
                 RelativeLayout.XConstraint="{ConstraintExpression Type=Constant, Constant=0}"
                 RelativeLayout.YConstraint="{ConstraintExpression Type=Constant, Constant=40}"
                 Text="Very long text in single line to be truncated at tail.  Adding extra text to make sure it gets truncated."
                 LineBreakMode="TailTruncation" />
          <Label BackgroundColor="Fuchsia"
                 RelativeLayout.XConstraint="{ConstraintExpression Type=Constant, Constant=10}"
                 RelativeLayout.YConstraint="{ConstraintExpression Type=Constant, Constant=80}"
                 Text="Very long text in single line to be truncated at tail.  Adding extra text to make sure it gets truncated."
                 LineBreakMode="TailTruncation" />
        </RelativeLayout>
      </ContentView>
      <ContentView Padding="16, 16, 16, 16" BackgroundColor="Gray" IsClippedToBounds="True">
        <RelativeLayout BackgroundColor="Navy" IsClippedToBounds="True">
          <Label BackgroundColor="Blue"
                 RelativeLayout.XConstraint="{ConstraintExpression Type=Constant, Constant=0}"
                 Text="Very long text in single line to be truncated at tail.  Adding extra text to make sure it gets truncated."
                 LineBreakMode="TailTruncation" />
          <Label BackgroundColor="Fuchsia"
                 RelativeLayout.XConstraint="{ConstraintExpression Type=Constant, Constant=0}"
                 RelativeLayout.YConstraint="{ConstraintExpression Type=Constant, Constant=40}"
                 Text="Very long text in single line to be truncated at tail.  Adding extra text to make sure it gets truncated."
                 LineBreakMode="TailTruncation" />
          <Label BackgroundColor="Fuchsia"
                 RelativeLayout.XConstraint="{ConstraintExpression Type=Constant, Constant=10}"
                 RelativeLayout.YConstraint="{ConstraintExpression Type=Constant, Constant=80}"
                 Text="Very long text in single line to be truncated at tail.  Adding extra text to make sure it gets truncated."
                 LineBreakMode="TailTruncation" />
        </RelativeLayout>
      </ContentView>
    </StackLayout>
  </ContentPage.Content>
</ContentPage>

VS2015 Version Info.cs

Microsoft Visual Studio Professional 2015
Version 14.0.23107.0 D14REL
Microsoft .NET Framework
Version 4.6.00081

Installed Version: Professional


Application Insights Tools for Visual Studio Package   1.0
Application Insights Tools for Visual Studio

ASP.NET and Web Tools   14.0.20626.0
ASP.NET and Web Tools

ASP.NET Web Frameworks and Tools 2013   5.2.30624.0
For additional information, visit http://www.asp.net/

Common Azure Tools   1.5
Provides common services for use by Azure Mobile Services and Microsoft Azure Tools.

GenerateUnitTest   1.0
Generates unit test code for methods in classes under test.

Microsoft Azure Mobile Services Tools   1.4
Microsoft Azure Mobile Services Tools

Microsoft MI-Based Debugger   1.0
Provides support for connecting Visual Studio to MI compatible debuggers

Multilingual App Toolkit   4.0.1466.0
Multilingual App Toolkit helps you localize your Windows Store app by providing file management, pseudo and machine translation, translation editor, and build integration. http://aka.ms/matinstallv4

NuGet Package Manager   3.2.0
NuGet Package Manager in Visual Studio. For more information about NuGet, visit http://docs.nuget.org/.

PreEmptive Analytics Visualizer   1.2
Microsoft Visual Studio extension to visualize aggregated summaries from the PreEmptive Analytics product.

SQL Server Data Tools   14.0.50616.0
Microsoft SQL Server Data Tools

Visual C++ for Cross Platform Mobile Development   1.0
Visual C++ for Cross Platform Mobile Development

Visual C++ for Cross Platform Mobile Development   1.0
Visual C++ for Cross Platform Mobile Development

Visual Studio Tools for Universal Windows Apps   14.0.23309.00 d14oob
The Visual Studio Tools for Universal Windows apps allow you to build a single universal app experience that can reach every device running Windows 10: phone, tablet, PC, and more. It includes the Microsoft Windows 10 Software Development Kit.

Xamarin   4.0.0.1697 (deffc90)
Visual Studio extension to enable development for Xamarin.iOS and Xamarin.Android.

Xamarin.Android   6.0.0.34 (3efa14c)
Visual Studio plugin to enable development for Xamarin.Android.

Xamarin.iOS   9.2.1.51 (3c0ec35)
Visual Studio extension to enable development for Xamarin.iOS.

iOS Screenshot

Android Screenshot