How to Use an Unlock Tool to Unlock Your Android Bootloader

Unlocking your Android device’s bootloader opens up a world of customization, allowing you to flash custom ROMs, install custom recoveries, and gain root access. While some manufacturers provide official methods, many users turn to unlock tools to simplify this process. This guide will walk you through the process of using unlock tools, focusing on two popular methods: using a Windows PC and using another Android device.

Understanding Bootloader Unlocking

Before diving into the “how-to,” it’s crucial to understand what bootloader unlocking entails and why you might want to do it. The bootloader is a program that runs before the Android operating system boots up. It’s responsible for initializing hardware and loading the OS. A locked bootloader restricts modifications to the system software, ensuring device security and stability as intended by the manufacturer.

Why Unlock Your Bootloader?

Install Custom ROMs: Custom ROMs are modified versions of Android that can offer enhanced features, performance improvements, and the latest Android versions even if your manufacturer no longer provides updates.
Root Access: Unlocking the bootloader is often a prerequisite for rooting your Android device, which grants you administrative-level control over your system, allowing for deeper customization and access to advanced apps.
Custom Recoveries: Custom recoveries like TWRP (Team Win Recovery Project) enable you to perform advanced operations like backing up and restoring your entire system, flashing ROMs and kernels, and more.

Warning: Unlocking your bootloader typically voids your device’s warranty. It also involves a factory reset, so back up all your important data before proceeding. Ensure you understand the risks before you begin.

Method 1: Windows PC Unlock (Windows-Android)

This method utilizes your Windows computer to send commands to your Android phone to unlock the bootloader. It’s a common and reliable approach.

Pre-requisites:

A Windows Computer (PC)
Your Android Phone (MOB) – The device you want to unlock.
A USB cable
Basic computer knowledge

Steps:

Download ADB & Fastboot and Device Drivers:
- Download the ADB and Fastboot tools. You can find readily available packages online by searching for “ADB Fastboot download.”
- Download the USB driver for your specific Android phone model from the manufacturer’s website. Installing the correct driver is crucial for your computer to communicate with your phone properly.
Prepare ADB & Fastboot Folder:
- Create a new folder on your PC and extract the contents of the downloaded ADB & Fastboot ZIP file into this folder. This keeps all necessary files organized.
Install Device Driver:
- Run the downloaded driver installer for your phone and follow the on-screen instructions to install it on your PC.
Open Command Window in ADB Folder:
- Navigate to the ADB & Fastboot folder you created.
- Hold down the Shift key, right-click within the folder, and select “Open Command window here” (or “Open PowerShell window here”). This will open a command prompt directly in the ADB folder, making it easier to execute commands.
Enable USB Debugging on Your Android Phone (MOB):
- On your Android phone, go to Settings > About phone > Software information (or similar, depending on your phone).
- Locate “Build number” and tap it 7 times rapidly. This will unlock Developer options.
- Go back to Settings > Developer options (you may need to search for it).
- Toggle the “USB debugging” option to ON.
Connect Your Android Phone to PC:
- Connect your Android phone to your Windows PC using the USB cable.
Check ADB Connection:
- In the command window on your PC, type adb devices and press Enter.
- On your phone, you should see a prompt asking to “Allow USB debugging.” Check “Always allow from this computer” and tap “Allow.”
- Run adb devices again in the command window. If your device is properly connected, you should see its serial number listed. If not, double-check your driver installation and USB cable connection.
Reboot to Bootloader and Unlock:
- In the command window, type the following commands one by one, pressing Enter after each:
```
adb reboot bootloader
fastboot flashing unlock
fastboot reboot
```
  - adb reboot bootloader: This command reboots your phone into bootloader mode.
  - fastboot flashing unlock: This is the command that initiates the bootloader unlock process.
  - fastboot reboot: This reboots your phone after the unlock process is complete.
  Note: On some devices, fastboot flashing unlock might not work. In such cases, try using fastboot oem unlock instead.
Confirm Unlock on Your Phone:
- After the fastboot flashing unlock command, your phone will likely display a confirmation screen. Use your phone’s volume and power buttons to navigate and confirm the bootloader unlock. The exact steps may vary depending on your device manufacturer.
Device Reset:
- Once confirmed, your device will perform a factory reset and reboot with an unlocked bootloader.

Method 2: Android-to-Android Unlock (Android-Android)

This method is incredibly useful when you don’t have access to a Windows PC. It leverages another Android phone to act as the host computer, using an OTG (On-The-Go) cable.

Pre-requisites:

An Android Phone (HOST) – This phone will act as the “computer.”
Your Android Phone (MOB) – The device you want to unlock.
An OTG Adapter – To connect the two Android phones via USB.
A working mind 🧠 😉

Features of Android-to-Android Unlock:

No PC Required: Unlock your bootloader anywhere, anytime, without needing a computer.
No Root Required on HOST Phone: The host Android phone doesn’t need to be rooted.
No Driver Installation: No need to worry about installing drivers on a PC.
App-Based Solution: Utilizes a readily available Android app for the entire operation.

Steps:

Install Bugjaeger Mobile ADB App on HOST Phone:
- Download and install the “Bugjaeger Mobile ADB” app from the Google Play Store on your HOST Android phone. This app provides ADB and Fastboot functionalities on Android.
Enable USB Debugging on Your Android Phone (MOB):
- Follow the same steps as in Method 1 (Step 5) to enable USB Debugging on the MOB Android phone (the device you want to unlock).
Connect Phones with OTG Adapter:
- Connect the HOST Android phone to the MOB Android phone using the OTG adapter and a USB cable.
Bugjaeger Automatic Launch & USB Permission:
- If the OTG connection is successful, Bugjaeger should launch automatically on the HOST phone.
- You might be prompted to grant Bugjaeger permission to access the USB device. Allow it.
Reboot to Bootloader via Bugjaeger:
- In the Bugjaeger app on the HOST phone, navigate to the “Commands” section.
- Tap on “Reboot Bootloader.”
- Confirm any prompts that appear on either phone to allow the reboot to bootloader.
Confirm USB Debugging in Bootloader Mode:
- While the MOB device is booting into bootloader mode, you might see another USB debugging confirmation prompt on the HOST phone. Confirm it.
Open Fastboot Shell in Bugjaeger:
- Once the MOB device is in Fastboot mode, go to the “Fastboot” section in Bugjaeger.
- Tap on the “Fastboot Shell” button. This will open a command window within Bugjaeger, allowing you to execute Fastboot commands.
Check Fastboot Device Connection:
- In the Fastboot Shell command window in Bugjaeger, type fastboot devices and press Enter.
- If the connection is successful, you should see your device’s serial number listed. If not, check your OTG connection and cables.
Unlock Bootloader via Fastboot Shell:
- In the Fastboot Shell, type the following commands one by one, pressing Enter after each:
```
fastboot flashing unlock
fastboot reboot
```
  - Again, if fastboot flashing unlock doesn’t work, try fastboot oem unlock.
Confirm Unlock and Device Reset:
- Follow the on-screen prompts on your MOB phone to confirm the bootloader unlock.
- Your device will then factory reset and reboot with an unlocked bootloader.

Troubleshooting Bootloader Unlock Errors

Sometimes, you might encounter errors during the bootloader unlocking process. Here are a few common issues and potential solutions:

Driver Errors (Windows Method): Ensure you have installed the correct USB drivers for your phone model. Try reinstalling the drivers or using drivers from the manufacturer’s website.
Device Not Detected (ADB or Fastboot): Double-check USB debugging is enabled, your USB cable is working, and connections are secure. Restart your computer and phone.
“Command Not Allowed” or “OEM Unlock Not Allowed”: Some devices require OEM unlocking to be enabled in Developer Options before you can unlock the bootloader. Check your phone’s Developer options for an “OEM unlocking” toggle and ensure it’s enabled.
Device-Specific Unlock Tools: Certain manufacturers, like Xiaomi, require specific unlock tools and processes. Research your device model to see if there are any manufacturer-specific instructions or tools required.

Conclusion

Unlocking your Android bootloader is a gateway to extensive customization and control over your device. Whether you choose the Windows PC method or the convenient Android-to-Android approach using tools like Bugjaeger, understanding the steps and potential issues is key to a successful unlock. Remember to always back up your data and proceed with caution, as bootloader unlocking carries risks and voids your warranty. Enjoy the freedom of your unlocked Android device!