Speaking as a programmer that has worked on adapting Android designs from mockups to reality this is probably a very useful article for would-be Android designers.

The "up button" description is a bit oversimplified but probably sufficient for an intro to design post.

Also fonts aren't exactly "device specific" as stated in the post. You can embed your own TTF or OTF fonts into your app as a resource and use them. There are some annoyances to doing this (particularly when viewed from a designer's standpoint, so I'll let the article slide on this one) like the XML layouts won't recognize these fonts but you can programmatically assign the embedded fonts to Android's various text controls very easily.

Of course the hardest part as always when dealing with fonts is the licensing which is slowly getting better but remains years behind the licensing of other digital media formats.

Also on the issue of fonts, he mentions that Droid Sans is popular (since it was previously the default system font) but he should probably have mentioned Roboto, which is the newer and IMO much nicer default font, which is also freely downloadable, the entire set of Android fonts are available for use under the Apache license and can be used freely even in non-Android contexts.