Cave is a Chrome Packaged Application used for testing web-based, desktop, or mobile prototypes.
The Citrix Application Validation Extension: Provides a centralized platform for prototyping and testing ideas Built using the Chrome App Platform Service-oriented, secure, and controlled Free, powerful, and easy to use
Most prototyping system allow you to build rough approximations of production-level software and then view them internally or on a staged web site. Cave allows you to rapidly build production-quality applications and automatically distribute them externally to anyone running the client. No other system we know of does these things, which we believe makes it unique.