Install Android 15 on Mi Mix 2S (AOSP ROM) – How to Guide!

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Want to install Android 15 on your Xiaomi Mi Mix 2S? You are in the right place. This comprehensive, step-by-step guide walks you through the complete process of flashing the unofficial LineageOS 22 custom ROM on the Xiaomi Mi Mix 2S (codename: polaris).

Even though Xiaomi has ended official software support for the Mi Mix 2S (which shipped with Android 8.0 Oreo and received Android 10 as its final update), you can breathe new life into this Snapdragon 845-powered device with Android 15. This custom ROM delivers the latest Android features, improved performance, better battery optimization, enhanced privacy controls, and a clean AOSP stock Android experience.

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Why Install Android 15 on Mi Mix 2S?

The Xiaomi Mi Mix 2S (released March 2018) was a flagship smartphone powered by the Qualcomm Snapdragon 845 processor with 6GB RAM and a sleek 5.99 inch IPS LCD display. Despite being a capable device, Xiaomi ended official software support at Android 10 (MIUI 12.5), leaving users stuck on outdated software with potential security vulnerabilities.

Installing Android 15 via AOSP ROM gives your Mi Mix 2S a second life with:

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Latest Security Patches
Protection against current known vulnerabilities and exploits.
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Better Performance
AOSP-based ROMs are usually leaner and faster than stock firmware.
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Extended Battery Life
Android 15 power optimizations can improve battery efficiency.
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Modern App Support
Run newer apps that require recent Android API levels.
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Android 15 Key Features You'll Get on Mi Mix 2S

Android 15 on Mi Mix 2S with AOSP ROM delivers a modern Android experience. Android 15 focuses on stability, privacy controls, and performance tuning. These are the key improvements you can expect from this update:

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Private Space

Sensitive apps can stay isolated behind an extra unlock boundary for improved privacy.
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Faster App Launch

Runtime and system optimizations reduce lag and improve app responsiveness.
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Background Efficiency

Smarter process handling lowers unnecessary battery drain in idle and standby states.
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Media and Audio Upgrades

Improved media pipeline behavior and cleaner handling for playback and recording tasks.
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Security Hardening

Stronger platform-level protections and safer defaults for modern apps.
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Refined System UI

Polished UX details across notifications, quick settings, and platform interactions.
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Important Warnings — Read Before Installing Android 15

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Device-specific ROM: This Android 15 custom ROM is ONLY for the Mi Mix 2S. Do not flash it on any other device — it will brick your device.

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Brick risk: Carefully follow every step in the correct order. Incorrect installation — such as flashing the wrong file, interrupting the process, or skipping the wipe — can permanently brick your Mi Mix 2S. TheUpgradeGuide is not responsible for any damage.

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Complete data wipe: Installing this custom ROM erases everything on your Mi Mix 2S — apps, photos, contacts, messages, and files. Create a complete backup before proceeding.

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Battery requirement: Charge your Mi Mix 2S to at least 50–60% before starting. An accidental shutdown during the flashing process can leave your device in a non-bootable state.

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Warranty void: Unlocking the bootloader and installing a custom ROM will void your manufacturer warranty.

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Pre-Installation Requirements for Mi Mix 2S

Make sure you have all of the following ready before starting the Android 15 installation on your Mi Mix 2S:

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Unlocked bootloader: Your Mi Mix 2S must have an unlocked bootloader. Use Xiaomi’s official Mi Unlock Tool if you haven’t done this. The process requires linking your Mi account and waiting approximately 7 days.

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TWRP Recovery installed: You must have TWRP Recovery installed on your Mi Mix 2S. Watch TWRP installation tutorial for Mi Mix 2S →

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Full data backup: Back up all important data — photos, contacts, messages, app data, WhatsApp chats, and files — before starting the installation. Consider using Google Backup and Google Photos for cloud backup.

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USB drivers installed: Install the appropriate USB drivers on your PC/Mac. These are needed if you’re using ADB/Fastboot for any part of the process.

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XDA Forum Thread: AOSP ROM for Mi Mix 2S — XDA Forum →

Always check this XDA Forum thread for the latest build updates, known bugs, required patches, firmware requirements, and community feedback before installing.

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Download Android 15 ROM & GApps for Mi Mix 2S

AOSP ROM ROM (AOSP-Based Android 15) for Mi Mix 2S

Google Apps (GApps) for Android 15 ARM64 – Choose One Package

apps LiteGApps (Android 15 ARM64)apps NikGApps (Android 15 ARM64)apps MindTheGApps (Android 15 ARM64)apps BiTGapps (Android 15 ARM64)

search Not sure which GApps to pick? Read our complete GApps compatibility guide ->

bolt Quick Installation Overview

Short on time? Here’s the 5-step summary of how to install Android 15 on your Mi Mix 2S. Scroll down for the detailed guide with screenshots.

  1. 1Download the AOSP ROM Android 15 ROM & GApps for Mi Mix 2S.
  2. 2Boot your Mi Mix 2S into TWRP custom recovery mode.
  3. 3Wipe system, vendor, data, cache, and dalvik cache partitions.
  4. 4Flash the Android 15 ROM zip followed by the GApps zip via TWRP Install.
  5. 5Wipe cache, reboot, and enjoy Android 15 on your Mi Mix 2S!
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Step-by-Step: Install Android 15 on Mi Mix 2S

1

install_mobile Install TWRP Custom Recovery on Mi Mix 2S

The first step is to install TWRP (Team Win Recovery Project) custom recovery on your Mi Mix 2S. TWRP replaces the stock recovery and allows you to flash custom ROMs, GApps, and create complete system backups. You’ll need a PC/Mac with ADB and Fastboot tools installed, plus a USB cable. If TWRP is already installed on your Mi Mix 2S, skip directly to Step 2.

2

file_copy Transfer the ROM and GApps Files to Your Mi Mix 2S

Download the Android 15 AOSP ROM ROM zip and your preferred GApps package from the download section above. Connect your Mi Mix 2S to your computer via USB and transfer both .zip files to the device’s internal storage root folder or SD Card. Remember the file location — you’ll need to find these files in TWRP later.

Transfer Android 15 AOSP ROM ROM and GApps zip files to Mi Mix 2S internal storage via USB
3

restart_alt Boot Mi Mix 2S into TWRP Recovery Mode

Disconnect the USB cable and power off your Mi Mix 2S completely. Once the device is off, press and hold the Power button + Volume Up button simultaneously until you see the TWRP logo appear on screen. Release both buttons when TWRP loads. If prompted, swipe to allow modifications.

Boot Mi Mix 2S into TWRP Recovery Mode using Power and Volume Up buttons
4

backup Create a Nandroid Backup of Your Current ROM

This step is critical for safety. In TWRP, tap Backup and create a complete Nandroid Backup. This creates a bit-for-bit copy of your entire current system — including the ROM, apps, data, and settings. If anything goes wrong during the Android 15 installation, or if you want to return to your previous ROM, you can restore this backup in minutes.

Detailed Nandroid Backup guide →

Create a full Nandroid Backup in TWRP before installing Android 15 on Mi Mix 2S
5

delete_sweep Perform a Factory Reset Using Advanced Wipe

Now perform a thorough Factory Reset to prepare your Mi Mix 2S for the Android 15 ROM. In TWRP, navigate to Wipe → Advanced Wipe. Check the boxes for Cache, Dalvik Cache, System, and Data partitions. Then Swipe to Wipe. This completely clears the old system files, user data, and cache — preventing conflicts with the new Android 15 ROM.

TWRP Advanced Wipe selecting Cache, Dalvik, System, and Data partitions on Mi Mix 2S
6

home Return to the TWRP Main Menu

After the wipe completes successfully, navigate back to the TWRP Main Menu by tapping the back arrow or pressing the home/center navigation button on your Mi Mix 2S. You should see the main TWRP screen with options like Install, Wipe, Backup, Restore, etc.

Navigate back to TWRP Main Menu on Mi Mix 2S after factory reset
7

system_update Flash the Android 15 ROM (AOSP ROM)

This is the main step. From the TWRP Main Menu, tap Install. Navigate to the folder where you saved the AOSP ROM (Android 15) ROM zip file. Tap the file to select it, then Swipe to Confirm Flash. The flashing process takes 2–5 minutes — do not touch anything or power off your Mi Mix 2S until it completes. You’ll see “Successful” when done.

Flash Android 15 AOSP ROM custom ROM zip file via TWRP Install on Mi Mix 2S
8

apps Flash the Google Apps (GApps) Package

Immediately after the ROM flash completes, do not reboot yet. Instead, tap “Install” again (or use the back button), navigate to your GApps zip file, and flash it the same way. This installs the Google Play Store, Gmail, Google Maps, YouTube, and other essential Google services on your Mi Mix 2S. Without GApps, you won’t have access to Google services or the Play Store.

Flash GApps package via TWRP immediately after Android 15 ROM on Mi Mix 2S
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cached Wipe Cache and Dalvik Cache

After the GApps flash completes, you’ll see a “Wipe cache/dalvik” button at the bottom left of the TWRP screen. Tap it and Swipe to Wipe. This clears any residual cached data and ensures a clean, error-free first boot of Android 15 on your Mi Mix 2S. Skipping this step can cause boot loops or app crashes.

Wipe cache and dalvik cache in TWRP after flashing Android 15 ROM and GApps on Mi Mix 2S
10

restart_alt Reboot Your Mi Mix 2S into Android 15

After the cache wipe completes, Press the Home Button, Click Reboot button from the main menu, Tap on System and Swipe to Reboot. Your Mi Mix 2S will now boot into Android 15 (AOSP ROM) for the first time! Important: The first boot typically takes 5–10 minutes as the system optimizes all applications. The screen may appear stuck on the boot animation — this is completely normal. Do not force restart during this process.

Reboot Mi Mix 2S into Android 15 AOSP ROM - first boot after successful custom ROM installation
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Android 15 Successfully Installed on Your Mi Mix 2S!

Congratulations! You’ve successfully installed Android 15 (AOSP ROM) on your Mi Mix 2S. Enjoy the latest Android features, improved performance, enhanced security, and a clean stock Android experience on your refreshed device!

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What’s Working & Not Working on Android 15 (Mi Mix 2S)

Based on the XDA Forum thread and community reports, here’s the current status of features on the AOSP ROM (Android 15) ROM for the Mi Mix 2S. Note: This may vary between builds, so always check the latest forum post.

check_circle Working

  • ✅ Phone calls & SMS
  • ✅ Wi-Fi & Hotspot
  • ✅ Mobile data (4G LTE)
  • ✅ Bluetooth & audio
  • ✅ Camera (photo & video)
  • ✅ GPS & location
  • ✅ Fingerprint sensor
  • ✅ NFC

cancel Known Issues

  • ⚠️ Minor camera quirks in some modes
  • ⚠️ Some hardware features may vary by build

Always check the XDA Forum thread for the most up-to-date bug list for your specific build version.

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Troubleshooting Common Issues

🔄 Stuck on Boot Animation (Bootloop)

If your Mi Mix 2S is stuck on the boot animation for more than 15 minutes, it may be bootlooping. Reboot into TWRP (Power + Vol Up), perform a full wipe (System, Data, Cache, Dalvik), and re-flash the ROM and GApps. Make sure you’re using compatible GApps for Android 15 arm64.

❌ “Error 7” or “Zip Verification Failed”

This usually means you’re flashing a ROM not built for your device. Double-check that the ROM zip is specifically for the Mi Mix 2S. Also ensure your TWRP version is up-to-date and compatible with Android 15 ROMs.

📱 No Mobile Data or Signal After Installation

You may need to flash the correct firmware (baseband/modem) before installing the ROM. Check the XDA Forum thread for the recommended firmware version for your build of AOSP ROM.

🔙 How to Restore Back to Stock ROM

If you want to go back to the stock ROM: (1) restore your Nandroid Backup via TWRP → Restore, or (2) download the official stock ROM from the manufacturer and flash it using the appropriate flash tool on your PC. This will completely restore your Mi Mix 2S to factory stock condition.

Frequently Asked Questions — Android 15 on Mi Mix 2S

Here are answers to the most commonly asked questions about installing and using Android 15 (AOSP ROM) on the Mi Mix 2S:

Is the Android 15 ROM for Mi Mix 2S stable enough for daily use?

The AOSP ROM (Android 15) ROM for the Mi Mix 2S is an unofficial build. Core features — including phone calls, Wi-Fi, mobile data, camera, Bluetooth, GPS, and the fingerprint scanner — work well in most builds. Some minor bugs may exist depending on the build version. We recommend checking the XDA Forum thread for the latest known issues before installing it as your daily driver.

Will installing a custom ROM void my Mi Mix 2S warranty?

Yes, unlocking the bootloader and installing a custom ROM voids the manufacturer warranty. However, since the Mi Mix 2S was released in September 2019, virtually all units are well past their warranty period, so this shouldn’t be a concern for most users.

Can I go back to stock ROM after installing Android 15 on my Mi Mix 2S?

Absolutely. You have two options: (1) Restore your Nandroid Backup through TWRP Recovery to return to your exact previous ROM state, or (2) Download the official stock ROM from the manufacturer’s website and flash it using the appropriate flash tool to perform a clean restore to stock firmware.

Which GApps package should I use with Android 15 on Mi Mix 2S?

You can choose from four popular options: LiteGApps (recommended for minimal footprint), NikGApps (offers granular control over which Google apps to install), MindTheGApps (balanced package), or BiTGapps (lightweight alternative). All must be the ARM64 variant for Android 15 (API 35). Read our complete GApps compatibility guide to choose the best option for your needs.

Do I need an unlocked bootloader to install Android 15 on Mi Mix 2S?

Yes, an unlocked bootloader is a mandatory prerequisite. Without it, you cannot install TWRP Recovery or flash any custom ROM. Use the manufacturer’s official unlock tool to request a bootloader unlock. The process typically involves a waiting period before the unlock is approved.

Does the Android 15 ROM support the Mi Mix 2S’s fingerprint scanner?

Yes, in most AOSP ROM builds for the Mi Mix 2S, the fingerprint scanner works correctly. However, functionality can occasionally vary between different build versions. If the fingerprint scanner isn’t working after installation, try updating to the latest build or check the XDA Forum for any required patches.

How do I update the Android 15 ROM on my Mi Mix 2S after installation?

To update to a newer build of AOSP ROM: Download the latest ROM zip from the LineageOS download page, transfer it to your device, reboot into TWRP, and flash the new ROM zip over the existing installation (this is called a “dirty flash”). Then wipe cache/dalvik and reboot. A full data wipe is usually not needed for minor updates, but always check the XDA thread for update-specific instructions.

Is the Xiaomi Mi CC9 the same as the Mi Mix 2S for custom ROM installation?

Yes, the Xiaomi Mi CC9 and Mi Mix 2S are the same hardware device sold under different names in different regions. The Mi CC9 was the Chinese variant, while the Mi Mix 2S was the global/international variant. Both use the exact same ROM, TWRP recovery, firmware, and kernel files. You can follow this same guide for either device.

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Have questions or ran into issues while installing Android 15 on your Mi Mix 2S? Drop a comment below and we’ll help you out! You can also get support from the XDA Forum community where the ROM developer and experienced users actively respond to questions.

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