Oppo A9 Custom Rom Review

Unofficial builds of Pixel Experience existed to replicate the Google Pixel UI.

The Oppo A9 is not developer-friendly. You will not find a CyanogenMod (LineageOS) nightly like on a Samsung or Xiaomi. However, Project Treble saved this phone from total obsolescence. With patience and the right GSI, you can temporarily resurrect your A9.

Before flashing, visit: XDA Developers Forum > Oppo A9 (Codename: Oppo Realme 5 family – they share hardware) and search for "GSI Treble Guide."

Custom ROMs for the Oppo A9 are a labor of love, not a guarantee. Proceed with caution, or simply sell the A9 and buy a Xiaomi or Pixel for a proper modding experience.

Have you successfully flashed a custom ROM on your Oppo A9? Share your experience (and your working patches) in the comments below.

Installing a custom ROM on an Oppo A9 (2020) is notably difficult because Oppo generally prevents users from unlocking the bootloader on its global devices . Without an unlocked bootloader, standard custom ROMs like cannot be installed through traditional methods. The Core Obstacles Locked Bootloader: Most global variants of the

are strictly locked. While some Chinese models may have unlockable bootloaders, users with international versions typically find themselves "out of luck" Limited Development:

Because of these hardware restrictions, there is very little official support from major ROM communities . You will not find the listed on official sites for popular ROMs Complex Rooting:

Even basic rooting on this device often requires complex workarounds, such as patching a Oppo A9 Custom Rom

file extracted from an OTA zip, rather than using a simple one-click tool. Potential Workarounds

Installing a custom ROM on an (such as the ) is a multi-step process that requires unlocking the device's bootloader—a step that can be difficult on many Oppo models due to manufacturer restrictions [22]. This process will completely erase all data

on your phone and may void your warranty. Proceed at your own risk. Phase 1: Prerequisites Backup Everything

: Sync photos, contacts, and files to the cloud or a PC, as your device will be factory reset [7]. Battery Check : Ensure your phone has at least 60% charge to prevent it from dying mid-flash [7]. Tools for PC : Download and install the latest Android SDK Platform-Tools (ADB and Fastboot) for your computer [14]. : Install the Oppo USB drivers so your computer can recognize the device [10]. Phase 2: Unlocking the Bootloader

The bootloader must be unlocked to allow any modifications to the system [14]. Enable Developer Options Settings > About Phone Build Number 7 times [10]. Toggle Settings Settings > Developer Options OEM Unlocking USB Debugging Boot to Fastboot : Connect your phone to the PC. In a command window, type adb reboot bootloader Unlock Command fastboot oem unlock fastboot flashing unlock

If Oppo has locked your specific model's bootloader, you may need to find a community-specific exploit on the XDA Forums Phase 3: Installing Custom Recovery (TWRP)

A custom recovery allows you to "wipe" the old OS and "flash" the new one [15]. Download TWRP : Find the official or stable TWRP file specifically for your Oppo A9 model (e.g., Flash Recovery : In fastboot mode, run: fastboot flash recovery twrp.img Boot to Recovery : Immediately hold Volume Up + Power fastboot boot twrp.img ) to enter TWRP [7]. Phase 4: Flashing the Custom ROM Wipe the System : In TWRP, go to Wipe > Advanced Wipe Dalvik/ART Cache, System, Data, and Cache wipe "Internal Storage" if your ROM file is saved there. Install ROM and select your downloaded ROM Swipe to confirm the flash. Install GApps (Optional) : If your ROM doesn't include Google services, flash the GApps .zip immediately after the ROM [7]. Reboot > System . The first boot can take up to 15 minutes [7]. Phase 5: Creating Your Own ROM (Advanced) If you intended to a ROM from scratch rather than just install one: Environment

: Set up a Linux build environment with at least 250GB of disk space [5.1]. Source Code Unofficial builds of Pixel Experience existed to replicate

to sync the Android Open Source Project (AOSP) or LineageOS source code [23]. command to select your device target and ) to compile the firmware [23]. Do you need help finding a specific Custom ROM

(like LineageOS or Pixel Experience) that is compatible with your exact Oppo A9 model number?

Do not attempt a custom ROM on Oppo A9 unless you have a full backup, a second phone for daily use, and experience with MTK brick recovery (using SP Flash Tool and auth bypass).

If you still want to try, share your exact model number (CPH1938? CPH1939?) and current ColorOS version. I can point you toward MTKClient-based bootloader unlock and GSI attempts – but no promises.

Would you like the ADB debloat list for Oppo A9 instead? It’s safer and will make your phone feel faster.

Oppo A9 2020 (CPH1937/CPH1938) is a challenging device for custom ROM development due to Oppo's historically restrictive bootloader policies and the device's age. While the hardware remains capable in 2026, official software support ended years ago, making custom ROMs or Generic System Images (GSIs) the primary way to access newer Android versions like Android 14 or 15. 1. Preparation and Prerequisites

Before attempting to flash any custom software, you must meet these non-negotiable requirements: Enable Developer Options : Navigate to About Phone and tap the Build Number 7 times. Then, go to Additional Settings Developer Options Enable OEM Unlocking : Inside Developer Options, toggle OEM Unlocking to the "On" position. Backup Everything : Unlocking the bootloader and flashing ROMs wipes all user data Hardware Check

: Ensure your device is at least 60% charged to prevent power failure during the flashing process. 2. The Bootloader Challenge Have you successfully flashed a custom ROM on your Oppo A9

Unlocking the bootloader is the hardest step for Oppo devices. OPPO Care: Forgot your password? Reset it with ease

Oppo A9 Custom ROM: A Comprehensive Guide

The Oppo A9, released in 2019, was a mid-range smartphone that offered impressive specs for its price. However, as with many Android devices, its software experience may have limitations. This is where custom ROMs come into play, offering a way to breathe new life into your device with the latest software, features, and performance enhancements.

Rating: 1/10

Pros:

Cons:

The Oppo A9 (2019) was a solid mid-range contender. With its massive 5000mAh battery, a decent MediaTek Helio P70 chipset, and a sleek design, it served the everyday user well. However, as years pass, software updates from Oppo have slowed to a halt. The device is stuck on Android 9 or 10 (depending on the region) with the dated ColorOS 6 skin.

For power users and tech enthusiasts, this is where the magic begins. Enter the world of Oppo A9 Custom ROMs. Installing a custom ROM can breathe new life into your aging device, offering better performance, modern Android features, and enhanced privacy.

But a word of caution before we dive in: MediaTek devices (like the Oppo A9, model CPH1937/CPH1939) are notoriously harder to mod than Qualcomm devices. The process is risky, voids your warranty, and can brick your phone if done incorrectly.

Because custom ROMs remove background tracking from Oppo/Google (depending on your GApps package), many users report an extra 1-2 hours of screen-on time on the Oppo A9’s already huge 5000mAh battery.