Hosting a REST WebService


I want to host my REST WebService to consume the data on a Xamarin App later on. Now my question is if you know where I could host my API for free. As it is just a test project I don´t want to pay for it. I have seen that firebase is free if you don´t reach some maxim, does anyone know a good tutorial about it? If you have other suggestions please tell me.

Thank you in advance! is a great place to start off with.