In this guide, we’ll walk you through the process of installing the Android 15 Custom ROM on the Samsung Galaxy A21s. If you’re eager to experience the clean, feature-packed Android 15, you’ve come to the right place. Google recently launched Android 15 for its Pixel lineup, followed by the official source code release for developers. This has led to the creation of custom ROMs based on Android 15 for Galaxy A21s, users can now enjoy an unofficial AOSP build of Android 15. Ready to transform your device with the latest Android features? Let’s get started!
Samsung Galaxy A21s Overview
The Samsung Galaxy A21s is having Samsung’s new Exynos 850 octa-core chipset coupled with RAM options from 3 to 6 GB. The phone has storage options to choose between 64 and 128 GB which is expandable by a MicroSD card up to 512 GB. The phone has a massive 5000 mAh of battery which can be charged using a 15w fast charger that comes in the box. It has a 3.5mm headphone jack as well.
The Samsung Galaxy A21s has a 6.5-inch HD+ 720p resolution super AMOLED display with a punch-hole camera cut out which Samsung calls its infinity-o display. The phone has an aspect ratio of 20:9 and the screen-to-body ratio is around 83%. It has a pixel density of around 270 Pixels per inch (PPI). The phone weighs around 192 grams due to its big battery and its thickness is around 8.9mm.
The phone runs on Android 10 based on Samsung’s One UI 2.0. It has features like dark mode, Android 10 gestures, and better one-handed usage. Galaxy A21s features a rear-mounted fingerprint sensor along with a facial recognition system for the security of the device. It also supports DUAL nano-SIM for connectivity.
The Quad-camera setup of the Galaxy A21s consists of a 48 MP main camera with PDAF, then there is an 8 MP ultrawide sensor, followed by a 2 MP macro and 2 MP depth sensor along with LED flash. It can record videos at 1080p @ 30fps. The phone has HDR and Panorama shooting options as well. At the front, there is a 13 MP selfie shooter in a punch-hole design, it can also record videos at 1080p @ 30 fps
Android 15 and Its Features
Google has officially rolled out Android 15, packed with a wide array of new features and significant improvements. This latest version promises enhanced productivity, stronger privacy protections, and smoother overall performance. Released on September 3, Google has made the source code available through the Android Open Source Project (AOSP). While Pixel devices are the first to receive the Android 15 update, it will soon be available on select devices from brands like Honor, iQOO, Lenovo, Motorola, Nothing, OnePlus, Oppo, Realme, Samsung, Sharp, Sony, Tecno, Vivo, and Xiaomi in the upcoming months.
Android 15 introduces several innovative features, including Private Space—which allows users to keep sensitive apps separate from the rest of the phone—and Improved Audio Image Descriptions. Additionally, there are new satellite connectivity options, an Earthquake Alert System, offline maps for Wear OS, and enhanced Bluetooth capabilities. Other key updates include Partial Screen Recording, Malicious App Blocking, App Archiving, Audio Sharing, improved low-light camera performance, better battery life, enhanced theft protection, a more user-friendly taskbar, and robust fraud and scam protection. Android 15 aims to deliver a more secure, versatile, and responsive user experience.
What’s Working and Known Bugs:
Whats working? Everything seems fine Known issues ? Please let me know with a proper logs
Steps To Install AOSP Android 15 on Galaxy A21s
This guide will walk you through the steps to install the AOSP Android 15 Custom ROM on the Samsung Galaxy A21s. If you’re looking for a clean, pure Android experience with the latest features and updates, you’ve come to the right place. Google has recently launched Android 15, and while it’s officially available for Pixel devices, the source code is also available for developers.
Before we dive into the installation guide, please ensure that you’ve met all the prerequisites mentioned below to avoid any issues during the installation process.
Pre-Requisites
Before proceeding, you are strongly advised to back up your device’s storage and all your essential files. This ensures that no data is lost in case anything goes wrong during the process. Following the steps carefully will help avoid any permanent damage or bricking of your device.
Charge Your Phone
Ensure your device has at least 50% or more battery before unlocking the bootloader or flashing the ROM to prevent any unexpected shutdowns during the process.
Download ADB and Fastboot Binaries
You can skip this part if you have already installed TWRP Recovery on your Galaxy A21s. For those who haven’t, ADB and Fastboot commands (platform-tools) are required to boot your device into bootloader mode, allowing you to perform the necessary flashing operations. ADB (Android Debug Bridge) establishes a connection between your device and computer, while Fastboot is a more advanced command-line utility for flashing and modifying Android devices.
You can download the ADB and Fastboot Binaries (Platform-Tools) here.
Download Samsung USB Drivers
You’ll need the appropriate USB drivers to ensure a successful connection between your Galaxy A21s and your computer. These drivers enable file transfers, flashing, and other operations between your devices.
You can download the official Samsung USB drivers here.
Unlock the Bootloader of Your Phone:
Unlocking the bootloader of your Samsung Galaxy A21s is essential before you can install any custom ROM. Make sure to follow Samsung’s official instructions for unlocking the bootloader. Unlocking the bootloader will wipe your device, so back up your data beforehand.
Install TWRP Recovery:
You must install TWRP Recovery on your phone to install any custom ROM on your device. After unlocking the bootloader, follow our guide to install TWRP Recovery on your Galaxy A21s.
Download Android 15 ROM:
You can download the Android 15 custom ROMs for the Samsung Galaxy A21s from the links below:
| CrDroid OS | Development Page |
| Lineage OS 22 | Development Page |
Download Android 15 Gapps:
Currently, there are no specific GApps packages officially released for Android 15. However, based on community feedback, NikGApps for Android 14 seems to be a reliable alternative. You can try using the NikGApps Core package from the Android 14 version to flash onto your Android 15 custom ROM.
You can download the NikGApps Core for Android 14 from the following link: Download NikGApps Core for Android 14
This package should provide the basic Google services, including the Play Store, on your Android 15 device. Since this is a workaround, there may be some compatibility issues, but it’s worth trying until an official Android 15-compatible GApps package is available.
Make sure to flash it right after the ROM installation during the TWRP installation process, and don’t forget to check for updates to GApps periodically.
Warning!
GetDroidTips is not responsible for any issues that may happen to your device if you flash it on another device and brick it. Do it at your own risk.
Instructions To Install:
- Connect your device to the PC via a USB cable. Make sure USB Debugging is enabled.
- Then, go to the platform-tools folder, type CMD in the address bar, and hit Enter. This will launch the Command Prompt.
- Execute the below command in the CMD window or enter recovery mode using the Volume and Power button combination to boot your device to TWRP Recovery:
adb reboot recovery
- Now head to the Install section and navigate to the downloaded vendor and firmware. Perform a right swipe to flash it.
TWRP Home - If you want Google Apps as well, you need to flash it at this instance. Go to Install, select the GApps ZIP file, and perform a right swipe to flash this file.
- When that is done, you may reboot your device. Head over to Reboot and select System.
The first boot after installing a custom ROM may take a bit longer than usual, so don’t panic if it seems slow. After the device boots, you will need to set it up as a new device, just like when you first got it.
Conclusion
If you’re eager to try the latest Android 15 OS on your Samsung Galaxy A21s, flashing this custom AOSP build is the way to go. While it is unlikely that the Galaxy A21s will receive an official Android 15 update from Xiaomi, this custom ROM will give you access to most of Android 15’s features and updates. However, as with any custom ROM, you might encounter some bugs or stability issues, so it’s a good idea to report them to the relevant XDA forum.
That’s all for this guide. We hope it helped you successfully install Android 15 on your Galaxy A21s. If you have any questions or run into any issues, feel free to leave a comment below. Good luck!