Cordova (Now Apache Cordova) is a great hybrid platform for building mobile apps targetting multiple mobile platforms Apple, Android or Windows mobile. But who cares about Windows mobile these days, so yes it is all about having one code base and deploys to Android and iOS.
HTML, CSS & JS
Not just a web application
Being able to have one code base and deploy to multiple platforms is a fantastic thing when it comes to mobile application development. With Cordova plugins available, the platform supports even accessing native APIs of mobile platforms such as camera and other sensors.
Not completely automated process
It is not completely automatic since if you write individual style information for each platform objective, you can not make Cordova automatically apply the transformation at compile-time; you have to change the linked style manually.
Lack of support
You might not have up to date supporting materials and proper support as for the native application development tools.
Configuration and use can be complicated as it requires the use of the command line.