AppFog vs AppScale: What are the differences?

AppFog: Simple PaaS for Java, Python, Node, .Net, Ruby, PHP, MySQL, Mongo, and PostgreSQL. AppFog provides the infrastructure web developers need to build apps without worrying about IT tasks or having to wait days to get servers ready for writing code. AppFog’s web application technologies include PHP, NodeJS, Ruby, Python, Java, .NET, MySQL, and PostgreSQL; AppScale: An open source implementation of Google App Engine. Run your applications in any cloud- public, private or hybrid. AppScale is a platform that allows users to deploy applications developed using the Google App Engine APIs over Amazon EC2, Rackspace, Google Compute Engine, Eucalyptus, Openstack, CloudStack, as well as KVM and VirtualBox.

AppFog and AppScale can be categorized as "Platform as a Service" tools.

Some of the features offered by AppFog are:

• Launches fast, runs fast- Varnish Cache and op-code caching run applications with less server load and accelerated performance.
• Reduces ops work- No more configuring servers, firewalls, Apache, security, or installing frameworks.
• Plays well with any SCM- Versioning is critical. AppFog is compatible with code management systems like git, svn, and mercurial.

On the other hand, AppScale provides the following key features:

• UI & Dashboard
• Manage Apps, Machines, and Logs
• Automated Data Persistence

AppScale is an open source tool with 2.39K GitHub stars and 273 GitHub forks. Here's a link to AppScale's open source repository on GitHub.