How to Install a Custom ROM on Android

Of all the ways you can customize an Android smartphone, installing a custom ROM is by far the most important. It can update an old device, let you focus on privacy and security, or just give your phone a brand new look. It’s a pretty hands-on process, but it’s also pretty easy as long as you follow the instructions. So let’s see how to install a custom ROM.
Why Install a Custom ROM?
The ability to use custom ROMs is one of Android’s great joys. A custom ROM contains a completely new version of the Android operating system. Being able to install – or flash, as it’s called – a ROM offers huge benefits.
- If your phone no longer receives updates from the manufacturer, you can use a ROM to get the latest version of Android.
- For phones with heavily customized software, you can install a ROM that gives you something closer to the “stock” Android experience.
- If you like the features of other manufacturers’ devices, you can often find ROMs that transfer them to yours.
- If your phone is slow or has low battery life, you can find ROMs optimized for speed or power consumption.
- You can also get degoogled ROMs which put more emphasis on protecting your privacy.
before you start
You need to do a bit of preparation before you can start. For the purposes of this guide, we’re going to assume that you already have all of these things in place.
- You need a custom recovery. It is a small software used to create a backup and flash a ROM. In this guide, we will use TWRP. A custom recovery will often be installed when you root.
- You need an unlocked bootloader. Most phones come with a locked bootloader and you need to unlock it before you can overwrite system files.
- Enable USB debugging. You can find the option to enable USB debugging in the settings panel. developer options on your smartphone.
- DisableSecurity. It’s a good idea to disable your security settings before flashing a ROM, especially if you’re using a fingerprint scanner.
- Back up your data. We’ll create a full backup during the flashing process, but it’s also convenient to just back up your data using the app. Titanium Backup. This requires root.
- Charge your phone or plug it in. You really don’t want your phone to run out of power halfway through flashing a ROM.
You can also prepare by checking out these common issues to be aware of when installing a custom ROM.
Download Custom ROM
You also need a custom ROM. Here it is important to make sure that you have one that is compatible with the exact model of your smartphone.
Obviously you’re not going to do anything as stupid as trying to flash a Motorola ROM on a Samsung phone, but if you have the US version of a Samsung smartphone, it might be quite easy to download a ROM designed for the international version of the same device by mistake. These could actually be classified as different phones. Be sure to get the right one!
The ROM will be downloaded as a .zip file. Save it somewhere on your phone’s internal storage. With most ROMs you may also need to download Google Apps (GApps) in a separate zip. You will normally get links to these from where you download your ROM.
How to Flash a Custom ROM
The best way to flash a ROM is to do it manually through your custom recovery. Although some Play Store apps automate the process, the best ones have long since been discontinued, while others are of varying quality.
The manual approach gives you full control over the process, and if something goes wrong, it will be much easier for you to jailbreak your phone if you understand what you are doing.
Boot into recovery
So let’s get started. Make sure TWRP is installed, then turn off the phone and boot it into recovery. How you do this differs on each handset, but normally involves holding down a combination of the power button and volume buttons and then following the on-screen instructions.
Flash the ROM
Once TWRP is launched, you are ready to start flashing the ROM. Here are the steps:
1. Create a Nandroid backup. This is what you will use to restore your phone to its previous state or to recover from any problem. Get to Backup and select the partitions you want to save. You can include them all, as it is possible to select which parts to restore when the time comes.
2. Slide the bar to start, then wait several minutes for the backup process to complete.
3. Return to the home screen and select to erase. Slide the bar to reset your smartphone (this will not erase your internal storage). This step is optional, but not erasing your smartphone can cause errors with your ROM (this is called a dirty flash). You don’t have to erase if you upgrade to a newer version of the same ROM.
4. Return to the TWRP home screen and select To install. Navigate to where you saved the ROM (the zip file).
5. Tap the zip file to select it, then swipe the bar to begin installation. The process may take a few minutes.
6. When complete, repeat step five with the GApps zip if necessary.
7. Now restart your smartphone.
Don’t panic if it seems to get stuck on the boot screen, as the first boot after flashing a ROM usually takes a little longer than normal.
After making a Nandroid backup, you should still be able to restore it to get your phone up and running quickly.
Once your phone has restarted, you’ll need to restore your data and apps (assuming you cleared data as mentioned above) and sign in to all your services again. Most ROMs are pre-rooted, so if you use Titanium Backup, it will work without any extra steps. You are now ready to enjoy your new software.
Choose a ROM to start
All you need now is to find a decent ROM to test. Lineage OS is the most popular and has both official and unofficial versions for the most devices. With its standard Android look, it’s the best place to start for most people.
Otherwise, we recommend that you browse the XDA forums for your specific device to find a good custom ROM. As long as you keep a recent Nandroid backup handy, there’s no harm in experimenting with several ROMs until you find the one that’s right for you.
Install a Custom ROM
Installing a custom ROM can seem daunting at first, but once you understand the steps involved, it becomes second nature. Custom ROMs open your phone up to a whole new world of customization, and they’re fun to play, too.
They might even save you money in the long run because you can get OS and security updates long after your phone has gone out of official support.
In this guide, you learned how to install a custom ROM on your Android device. If you have any questions or suggestions, let us know in the comments. Also consult this guide if you want to learn how to customize your home screen on android.