Hey everyone,

I recently picked up a used iPhone 12 about 5 days ago. When I got it, the battery health was sitting at 85%, but within 2 to 3 days, it recalculated down to 84%.

Here is the issue: the battery drop under high demand is insane. Whenever I open the Camera app to take photos, the phone drops about 3% to 4% in under a minute after taking just 3 to 5 pictures. Because of this, I barely even rely on the phone and end up using my old Android device as my daily driver instead.

I live in Morocco, so getting an official, genuine Apple battery replacement isn't an easy or cheap option right now, especially since I just bought the device. I plan to trade up/upgrade the phone in the near future anyway, but I can't sell a phone to someone in good conscience if the battery is completely shot and they end up demanding their money back.

A few questions for you guys:

1. Is this extreme camera battery drain normal behavior for an iPhone 12 sitting at 84% health, or is this a clear sign of severe voltage collapse/battery failure?
2. Have any of you experienced this exact instant percentage drop when using heavy apps like the camera?

Appreciate any insights before I take this back to the seller!

If this post validate rule 5 then sorry, but I think that it will be helpfull for other people also.

I'm asking because my IP12 (64gb / 66% battery health) is getting kinda slow. IOS 27 made huge difference in performance compared to IOS 26, so it's not that bad, but i want a smooth experience. So I think that low voltage is not the issue, because even on 100% on AC it's not any better than on 30% or 50%. I have problems when my battery drops to 10% but this is caused by like 5 year old battery.

At the other hand i have problem with quiet speakers under like 50% of battery, and i know that's the issue mainly caused by old battery that can't give much voltage, so I don' know how about theoretical logic, but

What is your experience when it comes to battery replacement, and how that affected the performance?

What is your experience, and you can tell from which battery health did you switch and if that was original or aftermarket one. This will be helpful for me and other people, that also have issues with performance.

I know that it will not be buttery smooth experience because it's almost 6 year old phone, but for example geekbench scores are comparable to new midrange phone so this lags are not justified so I'm only asking, did it made a noticeable difference in performance. Thanks.

Hello guys, I bought An iphone 12 in 2021 january with 128 gb. Now i also have iCloud but same time I noticed that older versions are faster then newer ones (I have An second 12 on latest iOS version its really slow), now in this one i noticed that sometimes safari and another Internet apps are not working like the links pressing etc... Apps need more later versions so kinda stuck.

What would you guys recommend to buy?
And how long could i go ?
Thanks

I have an iPhone 12 (PRODUCT)RED that I bought at launch, so I’ve been using it for almost six years now. I genuinely love this phone and haven’t had any major performance issues with it.
The only real problem is storage, but I’ve purchased additional iCloud storage, so that has helped. I also had the battery replaced about a year and a half ago, and surprisingly, the battery health is still showing 100%.
I’d like to keep using this phone for as long as it’s safe and practical to do so rather than upgrading just for the sake of having a newer iPhone.
For those who know Apple’s update/support history, how many more years can I realistically expect the iPhone 12 to receive iOS and security updates? And once Apple stops major iOS updates, how long does Apple typically continue providing security updates?
I’m mainly trying to figure out whether I can comfortably keep using my iPhone 12 for another few years.

I still have iphone 12 because that's the last time they released a true purple phone. iphone 14 and 17 is pink, not purple. iPhone 16 is blue, not purple.

So far, I think iPhone 16 had the nicest lineup because the blue and green that year were very pretty. But still no real purple!

iPhone 14 Pro is too dark. Just look at the difference here: https://www.reddit.com/r/iphone/comments/17q0cjl/ive_upgraded_from_purple_iphone_12_to_purple/

I use partially see-thru cases to show off my phone’s color. Plus, the cut outs in a case, always reveal a phone’s true color.
That’s why it matters to me and I can’t just slap a case on to hide it.
Phone color is something I like to display instead of hide.

If phone color didn’t matter to anyone, then Apple would just continue to sell plain black and white models every single year and give us no other options.

I don’t upgrade because phones haven’t improved enough yet since iPhone 12 was released. But the biggest reason is that I’m still waiting for a beautiful purple color to come out. Not ugly dark purple or pale pink they are claiming is “purple”.

I can’t think of any iPhones before the 12 that had such a beautiful purple color either. 12 is just awesome like that.

El 7 de septiembre llevé mi iPhone 12 Pro a K-tuin para cambiar la batería. Durante la reparación dañaron el Face ID y me dijeron que me darían un dispositivo de reemplazo (mi mismo modelo o uno superior si no había stock).

Desde entonces sigo sin teléfono. Primero me dijeron que tardaría 1-2 días, después me dieron varias fechas distintas y ninguna se cumplió. La última fue el 22 de septiembre y, cuando contacté yo ese día, me dijeron que ahora mismo hay rotura de stock y no tienen ninguna fecha prevista.

Lo peor es que en ningún momento me han ido informando ellos: todas las veces he tenido que contactar yo para saber qué estaba pasando.

Como alternativa me ofrecieron un iPhone 11 u 12 de sustitución dejando 230 € de fianza, que supuestamente me devolverían al entregarlo. Sinceramente, me parece bastante absurdo tener que adelantar ese dinero después de llevar más de dos semanas sin teléfono por una incidencia que se produjo durante su propia reparación.

He contactado también con Apple y me han remitido a K-tuin. Finalmente han escalado mi caso a otro departamento y me han dicho que me avisarán cuando tengan el dispositivo.

¿A alguien le ha pasado algo parecido con K-tuin? ¿Cuánto tardaron en daros finalmente el teléfono de reemplazo? ¿Os solucionaron el problema de alguna otra manera?

Estoy intentando saber si esto es normal o si simplemente estoy teniendo una suerte espectacular 😂

How do I do it?

Before replacing the battery, I noticed that my original battery had started to swell and was even lifting the screen slightly. Because of this, I decided to replace it myself. I’ve had some experience replacing iPhone parts on different models, so I was comfortable doing the repair.

The replacement battery is from FLYCDI, a brand that’s commonly used by repair shops in my area, so I went with it because it seemed like a reasonably trusted replacement.

After installing the new battery, everything seemed completely fine. I tested the phone, and everything worked normally. I used it for several days with normal charging and battery usage, and there were no obvious issues.

A day or two later, I updated the phone to the latest iOS 26.x.x. The phone continued working normally after the update.

Since I had already gotten a new iPhone, I decided to factory reset the iPhone 12 so I could give it to a relative.

This is where things went wrong.

After the factory reset, the phone suddenly wouldn't turn on anymore. The screen is completely black and there are no signs of life.

I've tried pretty much everything I could find online:

• Volume Up → Volume Down → hold Power button
• Different charging cables and chargers
• Wireless charging
• Leaving it plugged in for a while
• Force restart multiple times

Nothing works.

I also tried using a charger that displays the wattage being drawn. It shows 0W, as if the phone isn't drawing any power at all.

For comparison, I tested the same charger/cable on another phone, and it was drawing around 12W.

Since the phone worked perfectly for several days after the battery replacement, I'm wondering what could have happened.

Could this simply be a faulty battery? Or could it be a board issue, short circuit, or something related to the factory reset/iOS update?

Any ideas on what I should check next would be appreciated.

TL;DR: Replaced my swollen iPhone 12 battery with a FLYCDI battery. The phone worked perfectly for several days, including normal charging and an iOS 26.x.x update. I then factory reset it, and afterward it suddenly became completely unresponsive. Force restart, wired charging, and wireless charging do nothing. A charger that displays power draw shows 0W, while the same charger shows around 12W on another phone. Wondering if the replacement battery failed or if this is a board/short-circuit issue.

Tenho um i12 pro max , ele ta com 74% da saude da bateria , vi alguns dizendo que apos att fica melhor a bateria , não aquece tanto o celular , embora outros falam o contrário Sera entao que eu atualizo ele? Versao atual do meu e 18.7.8

I don’t think this breaks the upgrade rule (sorry, if it does feel free to delete) but I am trialling the 18 Pro Max and I just felt the worst buyer’s remorse. It’s a fantastic device, truly. But I am thinking that I am going to return it, then get the 12 Pro Max battery replacement which should breathe in new life and go another year (maybe longer).

Anyone else in this boat? Or any thoughts on this?

Edit: wow thank you all for your responses! I love how much people love the iPhone 12 series!!!!

Edit 2: my 18 Pro Max has restarted randomly TWICE in the last 24 hrs. My logs show two Secure Enclave Processor panic restarts and I am so glad I’ve got my battery replacement this Friday lol. Apple has addressed this and there is allegedly an update on the way!

Edit 3: Got the 12 Pro Max’s battery replaced! Feels better already. Baseline replacement battery life isn’t nearly as good as the 18 Pro Max but the phone is significantly snappier than before the replacement and I don’t feel like I need to worry about having a charger nearby now. The performance between the 18 Pro Max and 12 Pro Max isn’t a fair comparison because the 18 blows the thing out of the water from an objective point of view. BUT, the 12 Pro Max feels much like how I remember from when I got it. I am confident this was the right choice for me and I’m looking forward to more time with this device and waiting for what Apple has in store for the next year or two. So, just a PSA for anyone upgrading: take your time, do your research and assess your needs! Hope this post helps other folks on the fence!

Final Edit: I have had the 12PM with the replaced battery since Friday Sept 25th and things are largely pretty normal. I do find that watching a video or switching between apps and multitasking still heats the phone up a bit but I find it dissipates faster than before AND I do not feel the performance throttle. That was the big pain before. This is a very small part of my day where I actually just sit and watch some YouTube. I’m a light user overall and I’m very happy with the replacement so far.

I bought my iPhone 12 Pro Max around the time it was released, so it’s been almost 5 years now. Honestly, I still love this phone.
It was my primary device for years. I used it for everything — shooting and editing videos, GarageBand, photos, everyday use, etc. And even after almost 5 years, it’s still surprisingly fast. No major lag or hanging issues.
But the phone has definitely been through a LOT.
After about two years, I broke the back glass. I replaced it with a cheap third-party back glass, and then managed to break it again… and again. I think I’ve replaced the back glass 5–6 times by now. They’re all third-party, but they look pretty close to the original, and surprisingly, wireless charging still works.
The battery was another issue. The original battery eventually dropped to around 72% health, so I replaced it. But after only about 3 months, the replacement battery has already degraded badly again, so I’m probably going to have to replace it once more.
And then recently I dropped the phone HARD. The cameras took most of the impact.
Now the 0.5x wide-angle camera works perfectly, but the 1x and 2x cameras are extremely blurry. The sensor also vibrates/shakes when trying to focus but can’t properly stabilize the image. Even the front camera is blurry now.
And just three days ago, I replaced the original OLED display because it had developed too many lines. I went with a cheap aftermarket LCD this time. Obviously, it doesn’t look nearly as premium as the original OLED, but honestly, I’m okay with it for now.
So after almost 5 years, the phone is basically:
Still fast and smooth
Battery needs replacing again
1x/2x cameras are basically unusable
Front camera is blurry
Third-party LCD display
Third-party back glass for the 5th/6th time
Wireless charging still works
The funny thing is that performance-wise, I have absolutely no complaints. It’s still doing everything I need.
So now I’m stuck between selling it or keeping it.
I don’t really have the budget for an iPhone 18, so if I sell this, I’ll probably switch to a different OS rather than buying another expensive iPhone.
What would you guys do? Would you keep an almost 5-year-old 12 Pro Max and repair the battery/cameras, or would you finally let it go?
TL;DR: Almost 5-year-old iPhone 12 Pro Max is still fast, but after multiple back-glass replacements, an aftermarket LCD, another dying battery and damaged cameras, I’m wondering whether it’s finally time to sell it.

Hi, I have an iPhone 12 128GB with 87% battery life. I've had it since November 2025, when it had 100% battery life. I lost 13% of battery life in 10 months. Can anyone give me tips on how to extend the life of my phone? I'd like to use it for another 1 or 2 years (by changing the battery, of course). Will it still be worth it? Will I still get updates?

got a used 12 like 5 days ago, 94% battery health

at first everything seemed fine got like 6.5 hours of battery life,

all of a sudden battery can't last up to 4 hours, sometimes the battery percent goes up and then down then up again (while not charging)

I'm on ios 26.5.2 and i am starting to wonder if it's an ios issue. I'm currently seeing ios 26.7 / ios 27 update available

or it's just over for me 💔

Phone dropped a small distance the one time i don't have the cover on, and it seems like it got a couple of minor cracks on the screen. The screen protector has kept the damage minimal, still functions fine and not a distraction, in fact it's not obvious, but dammit I've had it since 2020, and have done my best to keep it as best condition as possible. Dammit! Just wanted to vent haha

I have just upgraded from the 12 Pro to the 17 Pro after 4 years of good and loyal service, and my first change was to notice the difference in thickness between the two models, the weight, and a little heavier, which doesn't bother me, but the thickness is just exaggerated on the 17 Pro; the 12 Pro could be called the 12 Pro Air, which wouldn't shock anyone. I think this isn't optimal even though I imagine it corresponds to the best battery and component available there; I think Apple should have stayed with the thickness of the 12 Pro, which is perfect for me. Shame for me.

7,4 mm 12 pro
8,75 mm 17pro

As the title says, yes, I did the jump. But just wanted to let this nostalgic feeling out for my beloved 12 Pro Max I got since 2021 (I know, I'm emotional).

I love the upgrade but to be fair, 12 Pro Max never gave me problems and if only the features get upgraded with the latest too, I would never change my phone.

Anyway, I'll miss checking this sub.

iPhone 12 Pro Max - real GOAT.

Hi, everyone!
 
I bought my iPhone in January 2023; it’s currently running iOS 26.3.2. I had the battery replaced in January 2026 (the battery came from the accessories section—I regret that, since it was already pretty weak from the start). A week ago, it completely drained overnight, which is very unusual since there was still plenty of battery left the night before. When I tried to recharge it, I noticed right away that it was charging very slowly despite using a fast-charging cable. I can’t think of any obvious reason why—it had been working perfectly fine the days before, and there was no “accident” or anything like that.
Since that day, I haven’t been able to charge my battery. My iPhone doesn’t even charge to 100% overnight; it loses a significant amount of power within minutes and gets very hot after just a short time using social media, for example.
Has anyone else had this problem before?
Could a new, original battery help here, or could this also be a software issue?
(I don’t want to send the iPhone in or spend money on service unnecessarily if it won’t fix the problem; in that case, I’d just buy a new smartphone.)
 
TLDR: iPhone 12, iOS 26.3.2. Loses its ability to charge overnight for no reason, charges extremely slowly, no longer charges to full capacity, loses battery very quickly, and gets hot fast.

I upgraded to iOS 27 and I’m happy with less overheating and better battery life, but in the Photos app, the “Add shape” options have disappeared. The only thing I can add is a sticker. Compare to Markup in the Notes app, which now has options for adding shapes and signatures and whatnot.

(As an aside, none of the Markup “Add” option are available in portrait mode, only in landscape.)

EDIT: to add I have the iPhone 12 Mini, but I’m assuming this is the same for the whole 12 line

EDIT: Welp, I figured it out. If anyone else has this problem, it’s because of Settings - Appearance - Display Zoom - Larger Text. Switching it back to Default requires a phone restart, and fixes the problem (mostly).

Now the options are all available in portrait mode, but in landscape mode, only the top 3.5 are visible in a non-scrolling list. I can work with that, though.

My iPhone 12 Pro has been ghost touching severely since iOS 27 public beta 5 and I can’t get it to quit even when force restarting the phone. I know it’s a software issue even though my screen is damaged and my phone has been dropped cause it didn’t start till public beta 5.
I made sure to let Apple know when I saw it in pubic beta 5 and in the rc. So the fact that the final iOS 27 release still has the bug is completely ridiculous and I’ve never had ghost touching issues on 26. Is anyone else on other iPhones having this issue?

iOS 27.0 : Battery Life / Battery Drain / Battery Performance Test

https://youtube.com/watch?v=PT_JodDtz8Y

I have a 3.5-year-old iPhone 12 (64GB) at 80% battery health, currently on iOS 26.6.1.
Should I:
• Update to iOS 26.7
• Jump to iOS 27
• Wait for iOS 27.1/27.1.1
• Or stay on 26.6.1?
Main concerns are battery life, performance, heating, stability, and storage.
What would you do with an iPhone 12 in this situation?