Because there are many terms in this world and on many occasions we have found that you ask us about it we have decided to make a small dictionary of terms as a reference and that it will be useful for users who are knowledgeable in the subject and will surely be useful as well. the basis for one of the most advanced users to collaborate by completing it.
Release / unlock
The first term we want to touch is to release, which is also known as unlocking or operator unlocking. When signing a contract with a mobile phone operator, our phone has a protection that prevents us from using a SIM from another operator before the end of our contract. Unlocking or unlocking the phone consists of removing this protection so that our device can be used with any telephone company/operator.
This release / unlock is a completely independent restriction to the operating system version that you have and will update your smartphone as many times as you do. That is, once released, usually, via a code offered by the operator, it is introduced in your terminal and is free.
ROM / firmware
We continue with what is a ROM and this time we have to point out that it is a term that is quite used in the computer / electronic sector and does not always have the same meaning. ROM is the acronym of Read-only Memory, read-only memory, but it is also known as ROM in the emulation segment the overturned version of a program or game.
In the case that touches us, ROM comes to be a version of Android that you can install on your mobile. That is, if we compare with a computer would be an image of the operating system just installed with all drivers and serial applications.
For this you will need to flash the terminal and, although it could be a lot of photos followed with flash to the terminal ;-), it is a process that usually involves the connection of the terminal to the computer in a specific mode of starting to change the software you have installed in your terminal for which you want to install.
That is, the terminal has a ROM, where the base operating system is installed, it is a memory that is maintained when the equipment is turned off and that once recorded is unalterable by the user and has been called ROM to what is what to record there / the operating system itself.
But, what do we need to flash our terminal? A prerequisite is to unlock the bootloader/bootloader unlock. A mobile works similarly to a computer in the way of starting. Once you press the power button, the terminal starts the boot process, without going into much detail, it starts with the bootloader. In theory, there are several ways to flash, one from the terminal itself if a custom Recovery is used, and another from a computer via adb / fastboot commands.
Bootloader and Recovery
The direct translation is bootloader and the truth is that these Anglo-Saxons usually nail this kind of buzzwords. By way of comparison with the boot of a computer, the bootloader becomes the post screen, that is when your computer shows the basic information, adds the RAM shows connected devices and either let you enter the BIOS / UEFI or continues with the boot of the operating system that you have installed.
We have said to enter the BIOS, well, because the equivalent in smartphones could be the Recovery allows performing some basic tasks such as cleaning the terminal data and leaving it at the factory directly. It is a separate partition and has nothing to do with the ROM itself. It can only be accessed from the boot and is usually accessed through a key combination that the Bootloader understands and then aborts the normal boot to make way for the Recovery.
Why is it necessary to release the bootloader to flash? The answer is obvious if we take into account that manufacturers, to avoid any security problems outside them, shield the boot by signing (with a single key) the packages that make up the updates of your operating system and also prevents the loading of the operating system with root functionality. That is, if you want to install any package, ROM or file that has not been offered by the manufacturer will not be possible.
What is the baseband? In a few words, we could call it the software that controls the data connections of our smartphone, usually come integrated with updates from the manufacturer and improve coverage or autonomy of the terminal if the manufacturer has detected a problem.
And last but not least, the key point that opens the whole world of possibilities that we have commented rootear / root a terminal. It comes to be a process equivalent to jailbreak in iOS, or simply to know the administrator password in a Linux / Windows / Mac machine. It is about getting the maximum privileges in Android to be able to install any application.
If you root an Android smartphone you get administrator/ superuser/root access and, therefore, you can perform functions such as access to application data, system directories, etc. However, you do not always work in that state, you keep working in user mode and root access is managed through an application (SU or SuperUser, for example) if an application needs root rights, the smartphone will ask us if we grant it. In a way similar to how a Windows / Linux / Mac computer asks us for permission to install an application or access the contents of protected folders.
How to install a new ROM
So, the process of flashing to install a cooked ROM (this is called an unofficial ROM, not offered by the manufacturer of your smartphone) is as follows: bootloader release, rooted, change of recovery to make a backup of your current installation, data cleaning, flashing ROM. This process is more complex and usually requires more intermediate steps depending on what mobile but to get a general idea is more than enough.
Many users will wonder why or why to flash a terminal and the truth is that there are ROMs cooked based on original ROMs, there are other very light as CyanogenMod , MIUI, Paranoid, which offer great features with a minimum RAM consumption and this implies more free RAM for your day-to-day multitasking, fewer slowdowns, etc.
And on many occasions we have very capable mobile terminals and that manufacturers stop supporting new versions of Android in the updates.
Most cases are usually due to economic issues and the investment they have to make in terminals that have already sold, something unprofitable for them a priori. In other occasions, we find mobile phones with very good RAM and it would be impossible to implement the new version of Android with the company’s software.
What terms are missing for this mini-guide? Any more than you do not know? You can participate in the comments and we will update the entry with new terms. I leave you some clue: kernel, APK, App2SD, sideload.