In a lengthy blog post , Google's developers recommended that the menu button no longer use. Since Android 3.0 Honeycomb, Google has said goodbye to physical menu buttons. These buttons are now replaced by an action bar, the menu button with three small dots on the right in the picture above. These three buttons are a temporary solution, preferably Google sees it completely disappear.
The action bar is like the replacement of the physical buttons. Since over 95 percent of the number of Android devices still use physical buttons are the most apps not yet optimized for virtual buttons only. Google recommends the action bar now possible to avoid when choosing these options are necessary as actual buttons in the action bar to implement.
The blog post makes clear why that indirectly menu button is so small compared to other virtual buttons. Google sees the bud is a stopgap that hopefully soon will disappear completely. However, it seems quite a time before this button will have effectively disappeared. First, many apps to be redesigned.