What is Sencha Cmd?
In short, Sencha Cmd is an executable that provides a series of further commands to assist with your Sencha application development. Under the hood, it comprises a number of third-party utilities and scripts that combine to provide this functionality. Here are a few of the things it bundles in its installation:
PhantomJS: This is used to manipulate web pages without using a browser interface
VCDIFF: This is a tool to work out the differences between a set of files
Closure Compiler: This is a tool to optimize and minify the JavaScript code
Jetty: This is a tool that provides a simple HTTP server
All of this is tied together with some custom glue from Sencha, supported by Apache Ant—a build tool commonly used in the Java world.
The result is a complex yet powerfully customizable tool. The use of Ant allows almost all of the features of Sencha Cmd to be tweaked and extended, while Sencha's additions provide a straightforward command-line interface to this power.
For the application...