xaml - Windows phone - Tile with picture in the middle and text at the bottom -

i'm working on windows phone app , , wanted make similar this.

i tried use square button add picture :

<button grid.row="1" horizontalalignment="stretch" verticalalignment="stretch" margin="10">                     <button.background>                         <imagebrush stretch="fill" imagesource="assets/marker.png"/>                     </button.background>  </button> 

but didn't find way add text @ bottom of button.

<button grid.row="1"          horizontalalignment="stretch" verticalalignment="stretch"          verticalcontentalignment="bottom" horizontalcontentalignment="left"         margin="10">                     <button.background>                         <imagebrush stretch="fill" imagesource="assets/marker.png"/>                     </button.background>        button text </button>