Microsoft Lumia 640 LTE Single Sim - Manual (Page 9)

Navigate by touch
To use your phone, simply swipe, tap, or tap and
hold the screen.
Swipe
Place your finger on the screen, and slide your finger
in the direction you want.
For example, to open the action centre, place a
finger at the top of the screen, and slide it down. To
hide the navigation bar, swipe up from the bottom
of the screen. To see the navigation bar again, swipe
up.
Zoom in or out
Place 2 fingers on an item, such as a photo or a web
page, and slide your fingers apart or together.
Tap and hold to open a menu
Place your finger on an item, until the menu opens.