Samsung J1 SM-J120F - Manual (Page 19)

Basics
19
Tapping
To open an app, to select a menu item, to press an on-screen button, or to enter a character
using the keyboard on the screen, tap it with your finger.
Tapping and holding
Tap and hold an item or the screen for more than 2 seconds to access available options.
Dragging
To move an item, tap and hold it and drag it to the target position.