See for example ScopeAR (a YC-backed company, YC Summer 2015 I think) for some use cases:<p><a href="http:&#x2F;&#x2F;www.scopear.com&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.scopear.com&#x2F;</a><p>video:<p><a href="https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?time_continue=9&amp;v=o_cD_jVaWJo" rel="nofollow">https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?time_continue=9&amp;v=o_cD_jVaWJo</a>