Thanks for your post. It answered a bunch of what I was wondering.
I looked at both the One and S4 in the store and noticed that a bunch of the screen was wasted just to include the virtual menu button. It seems like an oversight.
XDA Developers was founded by developers, for developers. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality. Are you a developer?