How To Use ADB and Fastboot Commands On Android

In this guide, we will look at how to use the ADB and Fastboot commands on Android needed to be able to put hands on your Android device to perform some essential functions on the device. First of all, we need to use two important tools that are Android Debug Bridge (ADB) and fastboot that is two programs that can be started via the Windows Command Prompt. Those who have installed the Android SDK on their computer with the Microsoft operating system will be able to find ADB and fastboot programs in the platform tools folder(android_sdk/platform-tools/), programs that can still be found anyway without necessarily installing the entire SDK package as you can install the minimal adb tool that contains only the files needed for ADB and fastboot and can be downloaded from the XDA website. ADB is a versatile command line tool that allows you to communicate with a device. The ADB command will enable you to smoothly perform actions on the device such as access to a Unix shell, useful to be able to execute different commands on a device.

Android debug bridge (ADB), is a versatile command line tool, which allows you to communicate with a device, easily operating certain device functions such as installing and debugging applications and accessing a Unix shell, useful for executing various commands on a device. Android debug bridge (ADB)  is a client-server program that includes the following components:

• Client- it is used to send commands from the developer’s computer and it is possible to call it from a command line terminal by sending an adb command
• Demon (adbd): used to execute commands on a device running as a background process on each device
• Server: manages the communication between the client and the daemon. On the developer’s computer, the server runs as a background process

How to use ADB and fastboot commands on Android- how ADB works and fastboot

Now let’s see how ADB works when starting the ADB client, the client must check first if an ADB server process is already running, so as to start the process if it is not detected. The server, once started, will connect to the local TCP port 5037, necessary to be able to communicate with the ADB client and “listen” to all the commands sent by the latter. The connections to all the devices that are running at that moment will then be imposed by the server, identifying the emulators and scanning ports with odd numbers in the range 5555 to 5585, the interval used by the first 16 emulators. When the server finds a daemon (adbd), it proceeds to set up a connection to that port. Why are scans of only odd ports made? The reason is that each emulator uses a pair of sequential ports- a port with an even number for console connections and an odd port instead for ADB connections. Here is an example:

Emulator 1, console- 5554  
Emulator 1, adb- 5555  
Emulator 2, console- 5556  
Emulator 2, adb- 5557  
and so on …

The emulator 1, as you can see in the example, is connected to ADB on port 5555, but also to the listening console 5554. Once the server has managed to configure the connections to all the devices, it is possible to use the commands ADB to access these devices. The server, managing the connections to the devices, and managing the commands from multiple ADB clients, allows you to control any device from any client or from a script.

How to use ADB and fastboot commands on Android- how to enable USB debugging on an Android device

How to enable USB debugging on an Android device. In order to use ADB with a device that is connected via USB, USB debugging must be enabled on the operating system settings on Android, under Developer Options. Starting from Android 4.2, the Developer Options item has been hidden by default, but making it visible again is very simple as you just go to Settings> About phone> Press 7 times with your finger on Build Number until you see a small window pop-up indicating that you have become a developer and options associated with it are now active. All you have to do is go back to the Settings, and you should now display the new Developer Options item on which you will need to click on it to access it. However, consider that this step is general, in some devices, the Developer Options screen may be located or be named differently. Once inside the Developer Options screen, you can enable USB debugging to have debug mode when connected via USB and consequently now you can connect your device via USB. To verify that the device is connected, from the directory android_sdk /platform-tools, you need to run adb devices, and if there is a connection, you will see your device listed as a “device”. When connecting an Android device via USB to the computer, in versions 4.2.2.0 and later of Android, the system will display a window asking whether to accept an RSA key, useful for allowing debugging through the computer in use. This is nothing more than a security system, which protects the user’s device by ensuring that USB debugging and other ADB commands cannot be performed unless the device can be unlocked and confirmed.

How to use ADB and fastboot commands on Android- how to connect an Android device via Wi-Fi instead of USB

How to connect an Android device via Wi-Fi instead of USB. Generally ADB is used to communicate with a device via USB, however, this connection cable is not the only way you can use it, in fact, it is possible to use ADB also via Wi-Fi, but after some initial settings made via USB as we will see in the following steps:

• Connect your Android device to the adb host computer to a shared Wi-Fi network (so they must use the same wireless network). During this phase, it is important that the access point has a firewall configured to support ADB
• If you need to connect to a Wear OS device, turn off Bluetooth on the paired phone
• Now connect the Android device to the host computer using the USB cable
• Set the target device for listening to a TCP / IP connection on port 5555 with the adb tcpip 5555 command
• Disconnect the USB cable from the computer
• You must now find the IP address of the Android device. To find it, follow the steps below (general guide for smartphones and tablets)  Settings  >  Device Information >  Status  >  IP Address ; for those who have Wear OS instead- on a Wear OS device, you can find the IP address in  Settings  >  Wi-Fi Settings  >  Advanced  >  IP Address
• Now you can connect to the device via its IP address with the adb connect  command device_ip_adress (your ip)
• Check now that your host computer is connected to the target device using the following command:

$ adb devices

List of devices attached

device_ip_adress – 5555 device

If you detect the ADB connection ok, otherwise if this is lost you do as follows:

• Make sure your host computer is connected to the exact same Wi-Fi network as your Android device
• Connect again with the adb connect command
• If the ADB connection does not work, reset the ADB host with the adb kill-server command and start again the steps to perform the wireless connection

Once the connection between computer and Android device is present, whether a USB or Wi-Fi connection is used, the ADB commands can be executed. Here are the following:

How to use ADB and fastboot commands on Android- Table 1 – Available adb commands and options

• -s– Install the app on the SD card.
• -d– Allows the downgrade of the version code (only for debugging packages).
• -g– Grant all runtime permissions.

$ ANDROID_PRODUCT_OUT = / out / target / product / generic 
adb sync

You can use the command  shellto send device commands via adb, with or without entering the adb remote shell on the device. To issue a single command without entering a remote shell, use the command like  shell this:

adb [-d | -e | -s serial_number ] shell_command shell

Or enter a remote shell on such a device:

adb [-d | -and | -s serial_number ] shell

When you are ready to exit the remote shell, press Ctrl + D or type  exit.

The binaries of the shell command are stored in the device file system in  /system/bin/.

Call activity manager (am). Within an adb shell, you can issue commands with the activity manager tool (  am) to perform various system actions, such as starting a task, forcing a process to be interrupted, transmitting an intent, changing the properties of the device screen and more. In a shell, the syntax is:  am command

You can also send a task management command directly from ADB without inserting a shell

adb shell am start -a android.intent.action.VIEW

How to use ADB and fastboot commands on Android- Table 2 – Available task management commands

Specify for intent arguments

For task manager commands that accept an  intentargument, you can specify the intent with the following options:

Call package manager (  pm)

Within an adb shell, you can issue commands with the package manager tool (  pm) to perform actions and queries on the app packages installed on the device. In a shell, the syntax is:

pm command

You can also send a package manager command directly from adb without entering a remote shell. For example:

adb shell pm uninstall com.example.MyApp

How to use ADB and fastboot commands on Android- Table 3 – Package management commands available

Call device policy manager (  dpm)

To help you develop and test your device management apps (or other companies), you can issue commands to the Device Policy Manager tool (  dpm). Use the tool to check the active administration app or change the status data of a policy on the device. In a shell, the syntax is:

dpm command

You can also send a device policy management command directly from adb without entering a remote shell:

adb shell dpm  command

How to use the ADB and fastboot commands on Android- Table 4 – Management commands for available device policies

Make a screenshot. The command  screencap is a shell utility for capturing a screenshot of a device’s display. In a shell, the syntax is:

screencap filename

To use the command screencapfrom the command  line, type the following:

adb shell screencap / sdcard / screen . pNG

Here is a sample screenshot session, which uses the adb shell to capture the screenshot and the pullcommand to download the file from the device:

$ adb shell
shell @ $ screencap / sdcard / screen . pNG
shell @ $ exit 
$ adb pull / sdcard / screen . pNG

To record a video. The command  screenrecord is a shell utility to record the display of devices with Android 4.4 (API level 19) and later versions. The utility records screen activity on an MPEG-4 file. You can use this file to create promotional or training videos or for debugging and testing.

In a shell, use the following syntax:

screenrecord [ options ] filename

To use  screenrecordfrom the command line, type the following:

adb shell screenrecord / sdcard / demo . mp4

$ adb shell
shell @ $ screenrecord - verbose / sdcard / demo . mp4
 ( press Control  + C to stop ) 
shell @ $ exit 
$ adb pull / sdcard / demo . mp4

The utility  screenrecord can record in any resolution and supported bit rate, while maintaining the display aspect ratio of the device. The utility records the native resolution and orientation of the screen by default, with a maximum length of three minutes.

Limitations of  screenrecord:

• Audio is not recorded with the video file.
• Video recording is not available for devices with the Wear operating system.
• Some devices may not be able to record with native display resolution. If you experience problems with screen recording, try using a lower screen resolution.
• Screen rotation during recording is not supported. If the screen rotates during recording, part of the screen is cut off during recording.

How to use ADB and fastboot commands on Android- Table 5 – Screenrecord options

ART profiles for apps. Starting from Android 7.0 (API 24 level), Android Runtime (ART) collects the execution profiles for the installed apps, used to optimize the performance of the app. You can examine the collected profiles to understand which methods are determined to be run frequently and which classes are used during app startup.

To produce a text form of the profile information, use the command:

adb shell cmd package dump-profiles package

adb pull / data / misc / profman / package .txt

Other shell commands

For a list of all available shell programs, use the following command:

adb shell ls / system / bin

The guide is available for most commands.

The following table lists some of the more common adb shell commands.

How to use ADB and fastboot commands on Android- Table 6 – Other adb shell commands

$ adb -s emulator-5554 shell 
$ sqlite3 /data/data/com.example.app/databases/rssitems.db 
SQLite version 3.3.12 
Enter ".help" for instructions

We have therefore seen  how to use the ADB and Fastboot commands on Android , all the commands have been recovered from the official source  developer.android.com and for some comprehension problems caused by the translation of the text found in the guide or to read all the descriptions of the commands in original language, I refer you to the reading of the  SOURCE.