What are some alternatives?
When comparing simperium and Google App Engine, you can also consider the following products
GUN - Self-hosted Firebase.
Heroku - Agile deployment platform for Ruby, Node.js, Clojure, Java, Python, and Scala. Setup takes only minutes and deploys are instant through git. Leave tedious server maintenance to Heroku and focus on your code.
Pusher - Pusher is a hosted API for quickly, easily and securely adding scalable realtime functionality via WebSockets to web and mobile apps.
OpenShift - OpenShift gives you all the tools you need to develop, host and scale your apps in the public or private cloud. Get started today.
Firebase - Firebase is a cloud service designed to power real-time, collaborative applications for mobile and web.
Dokku - Docker powered mini-Heroku in around 100 lines of Bash