CustomDroid
Samsung

Samsung Galaxy A21s

Samsung Exynos 850released 2020up to android 16latest android is 17
ro.product.devicea21s

also sold as Galaxy A21s · SM-A217F · SM-A217M · SM-A217N

Samsung Galaxy A21s
photo: LineageOS Wiki
Actively maintained

Released 2020, newest ROM build 6 days ago (4 ROMs still current). A phone that still gets updates keeps going long after its manufacturer stops.

Hardware

SoC
Samsung Exynos 850
CPU
Cortex-A55
GPU
ARM Mali-G52 MC2
Architecture
arm64
RAM
2/3/4/6 GB
Storage
32/64/128 GB
Screen
6.5" · 720x1600 · PLS LCD
Battery
5000 mAh
Network
2G GSM · 3G UMTS · 4G LTE
Released
2020

Sensors & features

  • 3.5mm jack
  • Accelerometer
  • Compass
  • Fingerprint reader
  • GPS
  • Gyroscope
  • Proximity sensor

Specs from the LineageOS wiki (CC BY-SA 3.0).

ROMs · 05

The Samsung Galaxy A21s (codename a21s) has 5 tracked custom ROMs on CustomDroid — including LineageOS, LineageOS for microG, /e/OS and 2 more, running up to Android 16. Each listing links to the project's own download and install guide, and was last checked against the projects' catalogues on 21 Sept 2026.

Tick “compare” on two or three builds to see them side by side.

Show
Android

RSS feed — subscribe to get new Samsung Galaxy A21s builds in your reader · JSON

Before you flash

Flashing generally means unlocking the bootloader, booting a custom recovery, wiping, then installing the ROM. Exact steps differ per device and ROM, so follow the Install guide for the one you pick, and back up first. Check what can break (banking apps, DRM, carrier features) and how to get back to stock before you start. Why flash a custom ROM · All guides

Custom recovery for this device: TWRP. Flash the one your chosen ROM's guide asks for — common recovery errors.

This is a Exynos device, so on Windows you'll want the Samsung Android USB driver before your computer will see it in fastboot. Which USB drivers you need.

LineageOS publishes a step-by-step install guide for this device: wiki.lineageos.org/devices/a21s

Timeline

  1. Jul 2026
    LineageOS, /e/OS, crDroid first tracked
  2. Sept 2026
    LMODroid, LineageOS for microG first tracked

Dates show when CustomDroid first indexed each ROM for this device, not when support originally launched.

ROM availability and links come from each project. CustomDroid indexes builds, it doesn't mirror them — always download from the official project, verify the file's hash/signature, confirm it matches your exact codename, and back up before flashing.