Are you saying that the Home, Back and Recent Apps buttons don't work any more? (androidcentral.com)
For starters, it would be nice to be able to swap the back and recent apps buttons without needing root access, which would be more ergonomic for a lot of folks. (android.gadgethacks.com)
A gray navigation bar sits at the bottom of every screen, with a rectangular recent apps button that pops up a menu that lets you switch to other programs. (laptopmag.com)