DevStudent

In this example i created a template with grid and textblock to use it in 2 longlist selectors in pivot app.

XAML code with template in pivot page

<phone:PhoneApplicationPage
    x:Class="PivotApp1.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"
    mc:Ignorable="d"
    d:DataContext="{d:DesignData SampleData/MainViewModelSampleData.xaml}"
    FontFamily="{StaticResource PhoneFontFamilyNormal}"
    FontSize="{StaticResource PhoneFontSizeNormal}"
    Foreground="{StaticResource PhoneForegroundBrush}"
    SupportedOrientations="Portrait"  Orientation="Portrait"
    shell:SystemTray.IsVisible="True">
    <phone:PhoneApplicationPage.Resources >
        <DataTemplate x:Key="GridTemplate">
            <Grid Background="{StaticResource PhoneAccentBrush}" Margin="5">
                <StackPanel VerticalAlignment="Bottom" Margin="5">
                    <TextBlock Text="{Binding LineOne}" TextWrapping="Wrap"/>

                </StackPanel>
            </Grid>
        </DataTemplate>
    </phone:PhoneApplicationPage.Resources>
        <!--LayoutRoot is the root grid where all page content is placed-->
    <Grid x:Name="LayoutRoot" Background="Transparent">

        <!--Pivot Control-->
        <phone:Pivot Title="MY APPLICATION">
            <!--Pivot item one-->
            <phone:PivotItem Header="first">
                <!--Double line list with text wrapping-->
                <phone:LongListSelector LayoutMode="Grid" GridCellSize="180,180" 
                                        
                                        Margin="0,0,-12,0" ItemsSource="{Binding Items}"
                                        ItemTemplate="{StaticResource GridTemplate}"
                                        >
                 
                </phone:LongListSelector>
            </phone:PivotItem>

            <!--Pivot item two-->
            <phone:PivotItem Header="second">
                <!--Double line list no text wrapping-->
                <phone:LongListSelector Margin="0,0,-12,0" ItemsSource="{Binding Items}"
                                        GridCellSize="150,150"
                                        LayoutMode="Grid" 
                                        ItemTemplate="{StaticResource GridTemplate}">
                  
                </phone:LongListSelector>
            </phone:PivotItem>
        </phone:Pivot>

    </Grid>

</phone:PhoneApplicationPage>