r/GalaxyS21

Got a used S21 Ultra from Amazon a couple of months ago. Overall condition was brand new except for the fact that the Bluetooth was way worse than my S9+ and the bottom of the screen flickers randomly, usually have to turn off the screen and back on for it to stop.

Also got a weird message in the update software section that my version isn't even supported. I kept the phone because I've tried two other sellers and the phones were worse than the one I kept.

Your current software version isn't supported. Visit a service center.

Update information

•OneUlversion:7.. •Android version: 15 •Current version:G998U1UESIHYL1/ G998U10YMIHYL1/G998USQSIHYL1 •Security patch level: December 1,2025

Hi everyone, dealing with an issue where my S21 + 5g will not update to a current version. I have an unlocked SM-G996U still running Android 12 on Tmo network. I know this phone is really old at this point, so I will be replacing in the next 6 months. However, I am unable to use many apps due to outdated software. I have tried using the OTA method as well as Smart Switch and neither will prompt the update. What else can I do?

So I've been thinking about upgrading my phone and I'm on a limited budget, but I've found a S21 FE that's not too bad of a price and it's still in excellent condition (obviously used since I'm too broke to afford new). Is it worth upgrading to the S21 FE or do I save up for a better phone? I do like the longevity of software support but performance is another thing. I've started noticing a lot of lag with just daily use on my A06 (Running One UI 8) and it's started making me consider the upgrade to the S21 FE. If anyone has any advice to let me know please

The other option I've got is the A53 5G that's still within my budget, are any of these 2 worth it or should I save up for a bit and get a better phone

Note: I know both phones are at the end of their software updates (not talking about security updates) and as much as I'd like to go higher than One UI 8, I'll trade that for performance

Edit: I've seen people mention that the green line issue on the S21FE is more common in the Exynos chips rather than the Snapdragon ones, not sure how true this is

so, the short explanations. i dropped my phone, then also dropped my phone in the toilet the same day... I turned it off and dried it out. i had previously had to re-glue the back on the device and water managed to get in around the cameras. so like i said, i tore it down and dried everything best i could, and used isopropyl to clean up some bits of corrosion that was already there prior to the water im guessing. now im trying to get my info etc off the device, ive tried connecting it to my PC however like I've said in my other post. my phone is bugged and wont let me file transfer etc to my pc. now the screen doesnt work and im trying to connect mouse and keyboard with HDMI to my tv to login that way... i can see my screen on the tv, but the keyboard doesnt do anything and the mouse turns on then immediately turns off... looking at the notifications on screen the phone says its charging only and tap for more options, and it also asks me to swipe and enter my pin. but as i said, i cannot as the screen doesnt work and neither do peripherals. i tried to remote unlock the device via Samsung smart things. but i cannot see the code or what the code is on the text message either as its blocked until i login. is there ANYTHING else i can try? ive tried blindly entering my pin on the keyboard with no hdmi and that also doesnt work. nor does just plugging in the mouse and clicking to even see the pin screen,

any and all help much appreciated

I have a good performing Verizon branded SD version S21+. It still performs very well with still good battery life after over 4 and a half years. My question is, should I upgrade to a newer version? My only concern is it isn't getting any more security updates. I only download apps from the app store, but I like using banking apps on it. Is this a big risk? Would it be reasonable safe to use it for another year or so?

My mother’s Samsung Galaxy S21 FE suddenly developed a green line on the display without any physical damage or fall.

Samsung has now officially denied any free support/replacement, saying the device is beyond ~3 years, even though this appears to be a widely reported issue with S21 series devices.

What’s even more frustrating is the way this was handled. For nearly a month, I was made to go in circles between support and service channels and had to explain the same issue more than 10 times, only to finally receive a denial.

This was a ~₹50,000 premium device, and Samsung advertises long-term software support, so users reasonably expect reliability beyond just 3 years.

I’ve already filed a complaint with National Consumer Helpline (GOI).
Complaint No: 9152340

Wanted to ask:
- Has anyone successfully escalated a similar case?
- Did legal notice or consumer court help?
- Is it worth pursuing further?

Would appreciate genuine advice from people who faced similar issues.

Hi,

I found my S21 and turned it on. It is with One UI 6.1.

I hesitate to update... what do you recommend?

Anyone know where to get an actual battery? I'm 0/2 on new batteries that arrive with 80% capacity. I can't seem to fine any actual original Samsung batteries. Much appreciated.

Hello Fellas I'm curious about how many 🔋 Cycles u have and the health of your battery.

S21 No Battery Replacements after all these years. I Have and S25 I wish it will last me as much as the S21.

Still Using S21 Perfectly Fine. Awesome Phone.

90% Battery Life

1178 Battery Cycles

Recently I got the S26+ as my main phone to replace my 4 year old S21 that died due to a swollen battery. However, I needed a second phone. For some odd reason I thought you couldn't replace the battery on the S21. I have no idea why I thought this but once I found out you could, I got a new battery and it's working perfectly again! I decided to make it my second phone and I'm oh so happy. I absolutely missed this phone! I love my S26+ but I find myself reaching for the S21 a lot of the time.

I just fixed s21 speaker to sound good, fuller and removed harshness using a discovered 32steps app.

Eq view: https://buzzheavier.com/zlu43iq1w01z

I plan to do a factory reset. To correct any issues that might have accumulated at the OS level. If I use smartswitch to back everything up to my PC, when I restore that stuff after the reset, does it write over deep system parts of the OS or leave the reset intact.

Hi. Anyone knows how to to flash Samsung phones? I need to flash my S21, SM-G991U to SM-G991U1 XAA unlocked firmware. Currently it's on Android 12 and One UI 4.1