8. How to switch between bottom navigation bar and gesture control on the M15? And how to use the gesture control?

You can go to Settings -> General -> Navigation control to switch between the bottom navigation bar and gesture control. The gesture controls are as below:

Return to Previous Menu: swipe from the lower left or lower right edge of the of the screen to the center;

Return Home: swipe up from the bottom edge of the screen;

Switch to Recent Tasks: swipe up from the bottom edge of the screen and hold;

Trigger In-App Functions: swipe from the upper left or upper right edge of the screen to the center