UserVoice - UserVoice integrates easy-to-use feedback, helpdesk, and knowledge base management tools in one platform that empowers users to speak and companies to understand.
Google App Engine - A powerful platform to build web and mobile apps that scale automatically.
Freshdesk - Freshdesk is a cloud-based customer support software that lets you support customers through traditional channels like phone and email, social channels like Facebook and Twitter, and your own branded community
Dokku - Docker powered mini-Heroku in around 100 lines of Bash
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.
Google Cloud Functions - A serverless platform for building event-based microservices.