It goes without saying for most Android enthusiasts that the side-navigation drawer is a hot point of contention right now. With the introduction of material design, Google emphasized information hierarchy heavily, giving advice in its design specifications on how to arrange just about everything, including side navigation. According to the specifications (and Googler Roman Nurik), the "correct" behavior for the side drawer is to slide in as a sheet of paper over the entire canvas, including the app bar or toolbar.
The issue with the new navigation drawer paradigm is that it has not been followed consistently by Google. It could be argued that Google implemented a placeholder drawer design in some places because the support libraries were not available, or to maintain fidelity with other drawers on pre-L systems since Android Lollipop is not actually released yet.Read More