I’d like to use a completely custom action bar (with my own text, font and background), but to the right I would like to preserve the standard menu icon that appears on tablets and devices that don’t have a hardware menu button (e.g. Samsung Galaxy).
Basically I would like to have this for tablets:

And this for regular phones that support the hardware menu button:

Assuming the question is “how to do this ?”, I’d answer that you should use style.
See this page.