What do you have in mind for using angluar JS and epi? But yes you can work with angular and episerver the same way you can with asp.net and angluar. Sadly there are no official docs but some quick googling I found this links that might be of interest:

http://www.frederikvig.com/2012/02/using-the-asp-net-web-api-framework-with-episerver/

http://www.asp.net/single-page-application

http://world.episerver.com/forum/developer-forum/-EPiServer-75-CMS/Thread-Container/2014/5/Episerver-website-as-Single-Page-Application/

http://www.episerver.com/globalassets/assets-website-structure/events/ascend/presentations/9.171_nolita2_soak-it-up---spa-time-for-devs.pdf

Thanks Eric. So basically, we need to expose the EPI data/content over REST API in order to consume it. Am I correct?

Yup. That would be my approach at least. Then you also need to build some kind of easy views to support editors. 

Yes you are correct. But remember when building an spa website like this editors should also be able to edit content in a nice way as if you did not have a spa template. But since we do not know how you would like to build your website it is hard to advice. But do not forget the editors :)

If you skip the onpage editing it is a bit easier but still you need them to understand the way you render the final result of  your website instead of the good old fashioned way of have templates representing each type of content.