Hosting for Free on Cloud Platforms?

[g4spow]

This looks awesome, really keen to use it on one of my own URLs but don't know much about Ruby on Rails.

Heroku offer a free plan but seems to sleep after 30 mins. Can you advise of any free options to host this? Perhaps on the major cloud platforms? Here are the free tier details:

https://aws.amazon.com/free/?awsf.Free%20Tier%20Types=categories%23featured
https://cloud.google.com/free/
https://azure.microsoft.com/en-us/free/

Perhaps Google App Engine or Azure App Service or Elastic Beanstalk? Not sure who these work with a getting a decent looking URL.