Google has updated its Material Design guidelines for Android and said that developers should consider placing a navigation bar at the bottom of their apps. The feature is termed ‘bottom navigation bar’ by the company and will be used to navigate to different sections within the app. The bar will be placed just above the on-screen navigation buttons. This system is similar to how iOS apps handle navigation. However, unlike on iOS, Google wants the bar to disappear when a user is scrolling up, and reappear when scrolled down.
Google has also said that the bottom navigation bar should only be used if an app offers three to five core areas. If there are only two areas, the company suggests developers stick to tabs and if there are six or more areas, developers should use the hamburger menu. Google has already started implementing the bottom navigation bar into its own apps. The Google+ app was updated with the feature a few months ago. A few weeks ago, the Google Photos app was updated to include a three-button navigation bar.