AppHarbor vs Modulus: What are the differences?

AppHarbor: Instantly deploy and scale .NET applications. AppHarbor is a fully hosted .NET Platform as a Service. AppHarbor can deploy and scale any standard .NET application to the cloud; Modulus: Hosting, Scaling, and Data for Node.js applications. Modulus is a premier Node.js hosting platform that provides a complete technology stack for application developers. This includes custom SSL, WebSockets, MongoDB, statistics, and more.

AppHarbor and Modulus belong to "Platform as a Service" category of the tech stack.

Some of the features offered by AppHarbor are:

• You push .NET and Windows code to AppHarbor using Git, Mercurial, Subversion or Team Foundation Server with the complimentary Git service or through integrations offered in collaboration with Bitbucket, CodePlex and GitHub.
• When AppHarbor receives your code it will be built by a build server. If the code compiles all unit tests contained in the compiled assemblies will be run. The result and progress of the build and unit test status can be monitored on the application dashboard. AppHarbor will call any service hooks that you add to notify you of the build result.
• If everything checks out the application is deployed and configured on AppHarbor application servers. AppHarbor can scale an application vertically and horizontally within seconds for better request throughout, performance and failover. AppHarbor balance load across all instances running that application. Scaling an application gives higher request thoughput, redundancy in case of instance failure and better performance.

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

• Simple Scalability
• Powerful Statistics
• Multiple Node Versions

"Has a totally free account option" is the primary reason why developers consider AppHarbor over the competitors, whereas "Easy to set up and scale" was stated as the key factor in picking Modulus.