The patent application is for an ordinary keyboard, such as MacBook The keyboard on Pro may have a movable special key. Take out that shift key, or iPad The newer "global" button in magic keyboard is your mouse.
Apple said in the patent application that the removable key can have a position sensor, so it can be operated as a pointing device of the computer. Therefore, the movable key structure can provide comfortable, portable and accurate pointer input for the computer input system. Indeed, you can move the key / mouse on the table to control the cursor more accurately.
Apple said that in some cases, portable computing devices such as laptops and tablets benefit from the use of peripheral mouse input devices. However, in this way, users have to carry a separate mouse on the computer, and when the computer already has a built-in pointing device, a separate device may be redundant.
Therefore, the purpose here is not to replace the touch pad, but to require more fine control. Although the patent application does not specify the use and benefits, you can imagine that a Photoshop user occasionally needs real accuracy when editing images. The details in the patent show two different ways. This key can be easily removed and used as a mouse.
Details in the patent show that this key can be easily removed in two different ways to use as a mouse. How physical keys work inside and outside the keyboard. In it, the key must react and respond like any other key on the keyboard. Then, when it is removed, it must have this position sensing ability. In addition, when it is removed from the macbook pro or other devices, it must have its own circuit and battery. It must do this, but it is also a very small mouse.