• Swipe from edges.
• Double tap on the status bar.
• Short/Long press on the physical keys.
• Home, Back, Recent Apps, Screen Off, Immersive Mode, etc.
• Launch of an application or a shortcut.
• Storage (saving screenshots)
• Camera (turning torch on)
• Location (displaying ads)
• Device Administrators (turning the screen off)
On Android 5.0 and above, it is possible to enable Immersive Mode with keyboard support. A tutorial can be found here: https://sites.google.com/view/aiogestures/tutorial