# Android Debug Bridge ⚙️

## Theory

Android Debug Bridge (adb) is a versatile command-line tool that lets you communicate with a device. The adb command facilitates a variety of device actions, such as installing and debugging apps, and it provides access to a Unix shell that you can use to run a variety of commands on a device.

## Practical

| Command                 | Description                                 |
| ----------------------- | ------------------------------------------- |
| `adb devices`           | List connected devices                      |
| `adb shell`             | shell on connected phone (then su for root) |
| `adb install "app.apk"` | install app on your phone                   |
| `adb backup <app>`      | backup \<app>                               |
| `adb logcat`            | logs on your phone                          |

## Frequent problems

Sometimes ADB can no longer connect to the mobile. There are several reasons for this.

### Make sure Developers options and USB debugging are activated

* Enable **Developers options**

1. Go to the settings of the Android device.
2. Go to the system settings.
3. Go to "About the phone".
4. Tap 7 times "build number".
5. The options for developers appear in the system settings.

* Inside Developers options, enable **USB Debugging**

> When in doubt, reboot (Confucious)

## Resources

{% embed url="<https://developer.android.com/studio/debug/dev-options>" %}

{% embed url="<https://developer.android.com/studio/command-line/adb>" %}