What does the remote control in the mobile phone mean? What's the use?

Can be achieved. Download 2 softwares to realize it. And it is rootless.

Control terminal: aerial image

Controlled end: AirDroid

Specific method: Install AirMirror on the mobile phone of the control terminal.

The controlled terminal installs AirDroid and logs into the same account at the same time.

Click the device on the AirMirror side.

At this point, you will be prompted that you are connecting. If the terminal you control is root, you can control it directly, such as sending text messages and taking photos remotely.