Make sure you included all scripts listed in the quick start guide. Specifically, angular-animate must be included to supply the animateReflow service.
<script src="//ajax.googleapis.com/ajax/libs/angularjs/1.2.10/angular.min.js"></script>
<script src="//ajax.googleapis.com/ajax/libs/angularjs/1.2.10/angular-animate.min.js"></script>
<script src="//rawgithub.com/mgcrea/angular-strap/master/dist/angular-strap.min.js"></script>
<script src="//rawgithub.com/mgcrea/angular-strap/master/dist/angular-strap.tpl.min.js"></script>