[Solved] Linux system cannot connect to Android Device

Troubleshoot

First, use the following command to install adb tool.

sudo apt-get install gvfs-backends
sudo apt-get install android-tools-adb

After installation, use the following command to check you device is connected. Of course you need to physically connect your device to computer.

adb devices

If you got the message:

List of devices attached
xxxxxxxxxxxxxxxx    device

It means your device is connected normally.

But if you got this message:

List of devices attached
xxxxxxxxxxxxxxxx    unauthorized

Maybe you can try the following steps to solve.

1. Remove the connection (PC-Mobile)
2. use adb kill-server to stop adb server
3. Cancel the USB authorization in the developer options of your mobile device
4. Reconnect

If the confirmation key appears on the phone, select "Always Trust This Computer". In this way, most mobile phone can be connected to the computer smoothly.