Web professional here. We hand code everything. A design tool might be fine for a one-off (IF you can get everything to look right in the tool!), but it doesn't allow the same control hand coding does. HOWEVER the main thing is one of maintenance. ANY web site that is the least bit popular will go through changes. This is much easier in a human written piece of pain html.

Hand written pages are lighter (IE: Smaller. That matters on a busy website).
Hand written pages can be written to be fully www3c compliant; I have yet to see a tool that can do that.
Also a lot of web frameworks use some type of templating system. Those are written manually.

I don't know where you live; but tell your son to pick up a programming language and a web framework. Two good ones are Ruby on Rails and Python with django.
Here in Atlanta they are dying for decent Ruby developers! Even if he is in high school or college, picking up coding at $50/hour beats working at McD's for $8.50...

http://android-developers.blogspot.com/2010/10/five-steps-to-future-hardware-happiness.html

the android SDK deal with this very well. Quote:"To make life easier every API includes a FEATURE_* constant. To control your app’s availability on the Android Market, you specify the features required for your app to work. I’d like to encourage you to add manifest Feature nodes for every API you use, specifying them as optional, or not, as appropriate using a manifest uses-feature nodes as shown below:"

I don't know a single other evolving platform that deals as well with these issues as android.