Demo: http://yankovsky.github.io/dropdown-angular/
You should add dropdown module to your application:
angular.module('sampleApp', ['ya.dropdown'])
And then you can use it like:
<div class='ya-dropdown'>
I am simple one level dropdown
<button class='ya-dropdown-toggle'>click me</button>
<div class='ya-dropdown-content'>
<ul>
<li>First item</li>
<li>Second item</li>
<li>Third item</li>
</ul>
</div>
</div>