Kurz Xamarin Forms

App.xaml

<?xml version="1.0" encoding="utf-8" ?>
<Application xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="ChatApp.Client.App">
  <Application.Resources>

    <!-- Application resource dictionary -->

  </Application.Resources>
</Application>

MasterDetailDemo.xaml

<?xml version="1.0" encoding="utf-8" ?>
<MasterDetailPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="ChatApp.Client.MasterDetailDemo"
             IsPresented="true">

  <MasterDetailPage.Master>
    <ContentPage Title="Master">
      
      <StackLayout>
        <Button Text="Detail 1" Clicked="Button_OnClicked" />
        <Button Text="Detail 2" Clicked="Button2_OnClicked" />
      </StackLayout>
      
    </ContentPage>
  </MasterDetailPage.Master>

  <MasterDetailPage.Detail>
    <ContentPage Title="Detail">

    </ContentPage>
  </MasterDetailPage.Detail>

</MasterDetailPage>

MasterDetailDemo.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using Xamarin.Forms;

namespace ChatApp.Client
{
    public partial class MasterDetailDemo : MasterDetailPage
    {
        public MasterDetailDemo()
        {
            InitializeComponent();
        }

        private void Button_OnClicked(object sender, EventArgs e)
        {
            var detail = new ContentPage()
            {
                Title = "Detail 1",
                Content = new Label()
                {
                    Text = "Detail 1"
                }
            };

            this.Detail = new NavigationPage(detail);
            this.IsPresented = false;
        }

        private void Button2_OnClicked(object sender, EventArgs e)
        {
            var detail = new ContentPage()
            {
                Title = "Detail 2",
                Content = new Label()
                {
                    Text = "Detail 2"
                }
            };

            this.Detail = new NavigationPage(detail);
            this.IsPresented = false;
        }
    }
}

packages.config

<?xml version="1.0" encoding="utf-8"?>
<packages>
  <package id="Microsoft.Bcl" version="1.1.9" targetFramework="portable45-net45+win8+wpa81" />
  <package id="Microsoft.Bcl.Async" version="1.0.168" targetFramework="portable45-net45+win8+wpa81" />
  <package id="Microsoft.Bcl.Build" version="1.0.14" targetFramework="portable45-net45+win8+wpa81" />
  <package id="Microsoft.Net.Http" version="2.2.22" targetFramework="portable45-net45+win8+wpa81" />
  <package id="Microsoft.Rest.ClientRuntime" version="0.9.6" targetFramework="portable45-net45+win8+wpa81" />
  <package id="Newtonsoft.Json" version="6.0.4" targetFramework="portable45-net45+win8+wpa81" />
  <package id="Xamarin.Forms" version="2.0.0.6482" targetFramework="portable45-net45+win8+wpa81" />
</packages>

<!-- do Package Manager Console napsat:
update-package -reinstall
-->