#install node.js before this command of course :)
#installing cordova on your system via node package manager
sudo npm -g install cordova
#creating the first app
cordova create hello com.example.hello HelloWorld
#adding the specific platform , you can have multiple platforms, for example android, blackberry and ios
cordova platform add ios
#running the app in the emulator, you have to have a native sdk installed
cordova emulate ios