Asus Transformer Pad TF300TG - Manual (Page 15)

ASUS Transformer Pad Manual 15
Locking the screen orientation
By default, your ASUS Transformer Pad screen automatically changes its
orientation from Landscape to Portrait mode and vice-versa depending on
the way you hold your ASUS Transformer Pad.
To disable this auto-rotate screen function, follow these steps:
1. Tap on the top right corner of the Home Screen to access the tablet
utilities.
2. Tap Settings > Screen.
3. Tap to deselect Auto-rotate screen.
You can also enable/disable the auto-rotate screen function from the
ASUS Quick Settings. For more details, refer to the section Settings.