click on the colors to change your pen to the corresponding color. click on pencil to change pen color to black and click on eraser to change to eraser. click on green flag to clear the hole page. take a screenshot to save picture. How to take screenshots: (Windows: press windows key and print screen key at the same time to take screenshot on Windows. Android: press and hold both power button and home button at the same time for 5 seconds to take a screenshot on Android.)
