Combine that with Adobe’s PhoneGap Build service, which lets you upload just the www folder of your project + a config file, and compiles apps for iOS, Android, BlackBerry, Windows Phone, Symbian and HP WebOS. It even has a developer API available.
I’ve used these two technologies recently for a project I’m on. We just needed a thin wrapper around our existing mobile site, so users could find the app from the app store. I basically just had to change all AJAX calls to use absolute links including the domain name, and change any regular forms to use AJAX instead. Then I built a Grunt task that compiled our EJS templates to static HTML, changed URLs as needed, zipped up the resulting files, and uploaded them to PhoneGap Build.
I can now run grunt phonegap:update to update the native app with the latest code from our mobile site!