Elebase is a back end as a service with geospatial capabilities.
Elebase's fully managed platform provides a powerful API and a rich set of tools to help you build more elegant applications faster and more efficiently. Spend more time building custom features that solve customer problems, and less time designing and maintaining back-end systems.
Google App Engine - A powerful platform to build web and mobile apps that scale automatically.
Napkin Beta - Backend in the browser
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.
Horizon - Horizon is a realtime, open-source backend for JavaScript apps.
Salesforce Platform - Salesforce Platform is a comprehensive PaaS solution that paves the way for the developers to test, build, and mitigate the issues in the cloud application before the final deployment.
Socket.io - Realtime application framework (Node.JS server)