Pony.fm/public/templates/tracks/_layout.html

<ul class="tabs">
	<li ng-class="{active: $state.includes('tracks.search')}"><a href="/tracks">Tracks</a></li>
	<li ng-class="{active: $state.includes('tracks.popular')}"><a href="/artists">Artists</a></li>
	<li ng-class="{active: $state.includes('tracks.random')}"><a href="/albums">Albums</a></li>
	<li ng-class="{active: $state.includes('tracks.random')}"><a href="/playlists">Playlists</a></li>
</ul>

<ui-view></ui-view>