How to tear off the toughened film

Although mobile phone manufacturers are equipped with cover glass to protect the screen, this cover glass is still very fragile, so many users will paste a toughened film on the screen of the mobile phone after buying a new mobile phone, to prevent the phone from falling to the ground and breaking the screen.
Toughened film although hard, brittle, but in fact it has a layer of internal film connection, when the user wants to replace or tear off the toughened film, as long as along the toughened film and mobile phone contact corner, gap, pull hard.