Question: how to use multi window in asus zenfone 5?
Answer: Please go to Settings -> System -> Gestures -> Check whether "Swipe up on Home button" is on/off. If not yet turned on "Swipe up on Home button" : ...  1-3. While in one of the Apps, press and hold the APP icon. 1-4. ...  1-5. ...  2-3. ...  2-4. ...  2-5. ...  3-2.