I am currently starting to build an PhoneGap application, I know the advantages of minifying code for browsers already. However, I was wondering if it was worth minifying my HTM
In general it is not worth minifying PhoneGap application. Minifying is beneficial for web application as it reduces size of each request.
With PhoneGap all your HTML/JS/CSS will be bundled into application package (which is compressed btw.) and downloaded once on application install. So there won't be any gains in speed.