➤ Android bootloader complete guide 🎮

Today we go back to school, we talk about the Android Bootloader: what it is, what it is for and why you need to unlock it. What is a bootloader? This is the question we will try to answer in this article. In simple terms, this is like the Windows bios, only unlike, it is possible to install a custom recovery, a kernel, a custom rom, but this after unlocking it.

What is Android Bootloader and what is it for?

The bootloader is one of the components that you can find in any operating system, whether desktop or mobile. Its mission is to make several checks before starting the operating system and make sure everything is okay, and give the operating system the instructions it needs to boot.

Therefore, when you start a computer or smartphone, the Bootloader first checks that everything is fine, that the components of the operating system are what they should be and that everything can boot correctly. And then it guides the operating system through the necessary steps to take during the boot process.

For practical purposes and to be easy to understand, when you press the power button on your computer or mobile phone, it turns on and starts up to load the operating system. First check the boot and recovery partitions, and if everything is correct, the operating system kernel runs to finish booting the phone. And if any process fails, an error message is displayed explaining why the system failed to boot.

The bootloader can be locked or unlocked and is developed by the device manufacturer. It is usually almost always locked, which means it can only boot partitions that have a digital signature from your mobile's manufacturer or operator.

Read: How to unlock bootloader on almost any android phone

With these security measures, the manufacturer ensures that you can only boot the version of the operating system that it has installed. This ensures that the user's mobile phone cannot be manipulated and that the data and code uploaded to the device are protected and what they should be.

But there are manufacturers who also decide to give users who buy their devices some freedom and to allow the Bootloader to be unlocked, which in Android is usually done with a combination of keys when possible. This opens the door for installing third-party ROMs, which are the alternate and modified versions of Android.

Why is it important to have the Bootloader unlocked on Android

As we explained above, by keeping it locked or closed, the manufacturer guarantees that the operating system of your device cannot be modified and that it always mounts the one created to run on it. So if this is a security measure, why is it important to allow unlocking the Bootloader on Android?

One of the main features of Android is freedom. Users can not only use the experience designed by the manufacturer, but in cases where it is unlocked, can be unlocked for making changes to the software installed on it.

Android has a whole world inside with so-called third-party ROMs, alternative versions that were not developed by Google or the manufacturers, but by independent groups of developers. With them, for example, you can install updated versions of android when the manufacturer has already decided to stop updating the operating system of a mobile. If your phone remained on Android 8, you could use a custom ROM to install Android 10.

One of the first steps to be able to install these ROMs is to first install a modified version of the recovery or recovery partition, from which to load the new version of the system. But as we have already told you, the Bootloader ensures that only partitions signed by the manufacturer can be loaded, so, for this, it must be unlocked.

A very clear example of the advantages that the Unlocked Bootloader can have in Huawei's Mate 30 and Mate 30 Pro. As you know, these devices are devoid of Google services or applications, which means the official Android application store and Google applications that have almost all devices, such as Google Play, Google Maps, Google Photos or Youtube.

If a user buys this mobile, a solution could be to unlock the Bootloader to install an unofficial version of Android.

Locked or unlocked?

To access these possibilities, you need to unlock it with a command. If we take the example of a manufacturer who markets an Android smartphone with a locked bootloader, it will be possible, depending on the encryption key used, to unlock it manually or automatically.

Generally, manufacturers do not release the unlocked bootloader, except in some cases. The official motivation is to avoid manipulation by users. Although the manufacturer must always give the user the opportunity to unlock the bootloader to give the device a second life.

Unlock bootloader?

Be that as it may, there are many brands that have adopted a policy that if you make profound changes to the system, the product warranty becomes invalid on the software part. When this is the case, it is best to inform yourself before undertaking this or that manipulation. Sometimes the result can be catastrophic and turn your phone into a brick.

In case a manufacturer voluntarily blocks it, the latter sometimes offers solutions to unlock it manually, like Sony, in particular. Sony warns that in case of manual release, the warranty on the software part becomes void.

Thus, some are stuck forever

Because? Because the encryption key chosen by the manufacturer to protect it is too strong to be bypassed. In the community, some developers have managed to unlock the bootloader
of their terminal, but it took several years.