Disclaimer: Installing a custom ROM voids your warranty and may risk bricking your device. Please follow each step carefully. Make sure to back up all important data efore proceeding.
I've always loved exploring ways to make my phone truly my own. After a few years with my Samsung Galaxy S9, I wanted a fresh experience without actually buying a new device. So, I decided to dive into the world of custom ROMs—a move that seemed a bit intimidating at first but has completely transformed how I use my phone. In this guide, I’ll walk you through the exact steps I followed to install a custom ROM on my S9. If you’re curious about unlocking new features, better performance, or simply giving your phone a fresh look, this tutorial is for you. Let's get started!
Prerequisites
Backup Your Data – Make sure to back up all data on your phone. Custom ROM installation will erase all data.
Battery Check – Ensure your Samsung Galaxy S9 is charged to at least 80% to avoid any interruptions.
Unlock Bootloader – This step will erase all data on your phone.
Download Tools:
Samsung USB Drivers: Install these on your computer.
Odin: This is the flashing tool used for Samsung devices.
Custom Recovery (TWRP): Download the correct version for the Galaxy S9 model (SM-G960F or SM-G960U).
Custom ROM: DotOs
Original firmware: Just in case
Step 1: Unlock the Bootloader
Enable Developer Options:
Go to Settings > About Phone and tap Build Number 7 times until Developer Options are enabled.
Go back to Settings > Developer Options and enable OEM Unlocking and USB Debugging.
Unlock Bootloader:
Power off your phone.
Hold Volume Down + Bixby + Power buttons to boot into Download Mode.
Press Volume Up to confirm.
Connect your phone to the computer and use Odin to unlock the bootloader.
Note: Unlocking the bootloader will wipe all data on the device.
Step 2: Install TWRP Custom Recovery
Download the latest version of TWRP for the Galaxy S9 on your computer.
Open Odin on your PC. In Odin:
Connect your Galaxy S9 in Download Mode.
You should see an "Added!" message in Odin if the connection is successful.
Go to the AP section and add the TWRP file (ending in
.tar).
Flash TWRP:
Uncheck the Auto Reboot option in Odin.
Click Start to flash TWRP.
Once complete, manually boot into TWRP by holding Volume Up + Bixby + Power buttons until the TWRP recovery screen appears.
Step 3: Backup Your Stock ROM (Optional but Recommended)
In TWRP, go to Backup.
Select Boot, System, and Data partitions, then swipe to create a backup.
This backup allows you to restore your phone to its current state if needed.
Step 4: Wipe Data and System Partitions
In TWRP, go to Wipe.
Select Advanced Wipe, then check Dalvik/ART Cache, System, Data, and Cache.
Swipe to wipe these partitions, which will prepare your device for the custom ROM installation.
Step 5: Flash the Custom ROM
Transfer the downloaded custom ROM ZIP file to your Galaxy S9 storage or an external USB drive (TWRP supports OTG).
In TWRP, go to Install.
Navigate to the location where you stored the custom ROM ZIP file, select it, and swipe to flash.
Step 6: Reboot and Set Up
After flashing, go to the Reboot menu in TWRP and select System.
Your Galaxy S9 will boot into the new ROM. The first boot might take a few minutes.
Troubleshooting Tips
Boot Loops: If the phone is stuck in a boot loop, reboot into TWRP and wipe the Cache and Dalvik/ART Cache, then reboot.
No OS Installed: If TWRP reports no OS, it may mean the ROM was not installed properly. You can re-flash the ROM or restore your backup.
Conclusion
Installing a custom ROM can bring new life to your Galaxy S9, offering a clean, customizable, and often updated experience. By following this guide, you can enjoy enhanced performance and features not available on the stock ROM. Be sure to choose ROMs from reputable sources and stay updated with the latest releases and security patches.
Happy flashing, and enjoy your custom ROM on your Samsung Galaxy S9 ✌️!
