namespace Bookmarks.Model
{
    public class Website
    {
        public string Title { get; set; }
        public string Url { get; set; }
    }
}

using System.Collections.ObjectModel;
 
namespace Bookmarks.Model
{
    public class WebsitesList : ObservableCollection<Website>
    {
        public WebsitesList() : base()
        {
            Add(new Website()
                {
                    Title = "Aymeric's blog",
                    Url = "http://www.aymericlagier.com"
                }
            );
            Add(new Website()
                {
                    Title = "Etudiant.ms",
                    Url = "http://etudiant.ms"
                }
            );
            Add(new Website()
                {
                    Title = "Julien Dollon",
                    Url = "http://blogs.dotnet-france.com/juliend/"
                }
            );
        }
    }
}

using Bookmarks.Model;
using GalaSoft.MvvmLight;
using GalaSoft.MvvmLight.Command;
using Microsoft.Phone.Tasks;

namespace Bookmarks.ViewModel
{
    public class MainViewModel : ViewModelBase
    {
        public string ApplicationTitle { get { return "Bookmarks"; } }
        public string PageName { get { return "My websites"; } }

        public RelayCommand BrowseCommand { get; set; }

        private Website _SelectedItem;
        public Website SelectedItem
        {
            get { return _SelectedItem; }
            set { _SelectedItem = value; }
        }

        private WebsitesList _Websites;
        public WebsitesList Websites
        {
            get { return _Websites; }
            set { _Websites = value; }
        }

        public MainViewModel()
        {
            if (IsInDesignMode)
            {
                // Code runs in Blend --> create design time data.
            }
            else
            {
                Websites = new WebsitesList();
                BrowseCommand = new RelayCommand(Browse);
            }
        }

        private void Browse()
        {
            if (SelectedItem != null)
            {
                WebBrowserTask wb = new WebBrowserTask();
                wb.URL = SelectedItem.Url;
                wb.Show();
            }
        }
    }
}

<phone:PhoneApplicationPage x:Class="Bookmarks.MainPage"
							xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
							xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
							xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
							xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
							xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
							xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
							xmlns:cmd="clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight.Extras.WP7"
							xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
							FontFamily="{StaticResource PhoneFontFamilyNormal}"
							FontSize="{StaticResource PhoneFontSizeNormal}"
							Foreground="{StaticResource PhoneForegroundBrush}"
							SupportedOrientations="Portrait"
							Orientation="Portrait"
							mc:Ignorable="d"
							d:DesignWidth="480"
							d:DesignHeight="768"
							shell:SystemTray.IsVisible="True"
							DataContext="{Binding Main, Source={StaticResource Locator}}">

	<!--LayoutRoot contains the root grid where all other page content is placed-->
	<Grid x:Name="LayoutRoot"
		  Background="Transparent">
		<Grid.RowDefinitions>
			<RowDefinition Height="Auto" />
			<RowDefinition Height="*" />
		</Grid.RowDefinitions>

		<!--TitlePanel contains the name of the application and page title-->
		<StackPanel x:Name="TitlePanel"
					Grid.Row="0"
					Margin="24,24,0,12">
			<TextBlock x:Name="ApplicationTitle"
					   Text="{Binding ApplicationTitle}"
					   Style="{StaticResource PhoneTextNormalStyle}" />
			<TextBlock x:Name="PageTitle"
					   Text="{Binding PageName}"
					   Margin="-3,-8,0,0"
					   Style="{StaticResource PhoneTextTitle1Style}" />
		</StackPanel>

		<!--ContentPanel - place additional content here-->
		<Grid x:Name="ContentGrid" Grid.Row="1">
			<ListBox x:Name="MainListBox" Margin="0,0,-12,0"
					 ItemsSource="{Binding Websites}"
					 SelectedItem="{Binding SelectedItem}">
				<i:Interaction.Triggers>
					<i:EventTrigger EventName="SelectionChanged">
						<cmd:EventToCommand Command="{Binding BrowseCommand}" />
					</i:EventTrigger>
				</i:Interaction.Triggers>
				<ListBox.ItemTemplate>
					<DataTemplate>
						<StackPanel Margin="0,0,0,17" Width="432">
							<TextBlock Text="{Binding Title}" TextWrapping="Wrap"
									   Style="{StaticResource PhoneTextExtraLargeStyle}"/>
						</StackPanel>
					</DataTemplate>
				</ListBox.ItemTemplate>
			</ListBox>
		</Grid>
	</Grid>
</phone:PhoneApplicationPage>