Do I need to register app.com and api.app.com?

Question

I am developing a rails api to work with angularjs FE app and with several other mobile application. Since I have developed separately, do I need to host separately ? If so then how to manage domains?

Answer 1

api.domain.com is a sub-domain. You need to add an A-Record of this in your domain and point it where ever you want to.

Answer 2

You can host in sites like heroku.com as they do provide free tier for basic usages. They also do provide free domain for your rails app.