How to Turn on/off Screen rotation in Samsung smartphones?

Step 1. Swipe down on the screen to open the Quick panel.

Step 2. If a gray Portrait or Landscape mode icon is displayed, tap the gray icon to activate Auto rotate. The icon will glow blue when enabled. 

If the Auto rotate feature is already activated, you don't need to select anything.

Portrait mode holds the screen upward and Landscape mode holds the screen sideways. Both icons look like locks and are gray when enabled. When the screen is locked in Portrait or Landscape mode, the screen no longer rotates when you rotate your phone.

When you tap the active blue Auto rotate icon, the icon will switch to a gray Landscape or Portrait mode and the screen will stay that way (upward or sideways).

The Home screen does not rotate to landscape mode by default, but if you prefer to view your phone sideways, you can set the Home screen to landscape mode. Follow the steps below to set your Home screen rotation.

Step 1. Launch the Settings app, and then tap Home screen.

Step 2. Tap the switch next to Rotate to landscape mode.

Step 3. Now, the Home screen will also rotate to landscape mode, once you turn your phone sideways.