Understanding Custom Roms

Amit Gujar
4 min readMay 20, 2020

Android is a mobile operating system based on a modified version of the Linux kernel and other open-source software, designed mostly for touchscreen mobile devices such as smartphones and tablets. Android is the favorite OS of developers because they can take its code, add features, and build their own operating system images for Android phones and tablets. If you using android then you must have heard the term like custom rom in your friend circle or elsewhere. Today's article is all about Custom ROMs and it’s related main queries.

source: zerouniverse

What is Custom ROM?

Developers other than the OEMs modify the code of android firmware and re-release it as a Modified ROM or Custom ROM. ROMs are developed by the Android community, oftentimes by a group of core developers who do this purely out of a passion for modding. This means that most are completely free. Custom ROMs are available for any type of device running Android.

Is it safe?

Now those who just entered the world of custom rom, they always have one question of safety and honestly nothing wrong in that. It is obvious to have such a question because custom ROMs are a modified version of android. Safety depends on what kind of custom ROMs you are gonna use. I am highly recommending to use ROMs developed by well-known organizations if you don’t know their name then just search it on the internet but never download ROMs if the developers are unknown.

source: blog.omni-bridge.com

Why use?

Well, I am not suggesting that everyone just starts to use custom ROM but if you wanna dive deep in android modifications then you should use them. When OEM launches new devices they just drop the software support for old devices and whenever the new version of Android comes out your device fails to get that update in such cases custom ROMs are helpful. Custom ROMs can improve your device functionality, performance, stability, allow you to do any modifications plus you can get in contact with community, devs directly through social media if you need any fixes or solutions to your problem.

The root is necessary?

NO..!!! you don’t need to give root access for just installing custom ROMs because they can be installed through third-party recovery software and they don’t require root access. All you have to do is unlock the bootloader of your device to install third-party recovery.

What is a bootloader?

In simple terms, a bootloader is a bunch of code that runs on a device before the operating system starts up. This low-level code contains the instructions that tell a device how to start up and find the system kernel. To install third-party recovery you need to unlock it. Some OEMs (Huawei) don't allow you to play with a bootloader, so you can’t install custom ROMs until they give permission (Xiaomi).

source: CyanogenMod

What is Recovery?

Recovery is basically software which allow you to flash ROM, default recovery in a device is known as stock recovery which is developed by OEMs. Stock recovery allows you to flash stock ROM but not custom ROM, therefore you need third party recovery to get the job done.

source: Digitaltrends

Will it affect the warranty?

This totally depends on OEMs, for example in some cases unlocking boot-loader may not void your warranty (Xiaomi, Realme, Oneplus). In some cases, you will lose your warranty (Asus, Sony, Samsung, Motorola).

Will it brick my device?

The process of installing custom ROMs is can be very easy/hard totally depends upon your knowledge. If you do things as per instructions then nothing strange will happen but if you don’t then surely your device will die.

Can I lock the bootloader after installation?

No…!!! You shouldn't try to lock the bootloader after installing custom ROM. If you do so then your phone will go into a red state where the device freezes on startup and gets restarts in every 30 secs. If you already did then don’t panic just boot your device into fastboot and unlock it again.