Apple Releases iOS 12.1.2 for iPhones With eSIM Bug Fixes

by

Apple today released iOS 12.1.2, the fourth update to the iOS 12 operating system since its September launch. iOS 12.1.2 comes just two weeks after the release of iOS 12.1.1, and one week after Apple seeded the first iOS 12.1.2 beta to developers.

The iOS 12.1.2 update is available exclusively on the iPhone and it can be downloaded over-the-air in the Settings app. To access the update, go to Settings > General > Software Update. As with all iOS updates, iOS 12.1.2 is free to download. iPads and iPod touch models continue to run iOS 12.1.1, the prior version of iOS 12 released on December 5.

appleesim
According to Apple's release notes, iOS 12.1.2 is a bug fix update that focuses on addressing issues with eSIM activation and a cellular connectivity issue in Turkey. From Apple's release notes:

iOS 12.1.2 includes bug fixes for your iPhone. This update:

- Fixes bugs with eSIM activation for iPhone XR, iPhone XS, and iPhone XS Max

- Addresses an issue that could affect cellular connectivity in Turkey for iPhone XR, iPhone XS, and iPhone XS Max

The timing of the iOS 12.1.2 release is curious as Apple often seeds more than one beta before launching a software update. It's likely that iOS 12.1.2 is addressing a bug that Apple did not want to wait to fix.

Today's iOS 12.1.2 release may also include software tweaks in China that remove patented Qualcomm functionality. A Chinese court last week issued an iPhone sales ban on certain devices in China after ruling that Apple had infringed on two Qualcomm patents related to resizing and reformatting photos and managing applications using a touch screen when using apps.

Apple said it would issue a software update for iPhone users in China to address "the minor functionality of the two patents at issue in the case."

eSIM functionality was first introduced in the iOS 12.1 update and expanded with iOS 12.1.1. In the U.S., T-Mobile, Verizon, and AT&T are all now supporting the eSIM feature, as are multiple other carriers around the world.

Update: The iOS 12.1.2 update is now available for download.

Update 2: This post has been updated to reflect the fact that it is only available for the iPhone.

Related Forum: iOS 12

Popular Stories

iphone air thickness

Apple Said to Cut iPhone Air Production Amid Underwhelming Sales

Friday October 17, 2025 8:29 am PDT by
Apple plans to cut production of the iPhone Air amid underwhelming sales performance, Japan's Mizuho Securities believes (via The Elec). The Japanese investment banking and securities firm claims that the iPhone 17 Pro and iPhone 17 Pro Max are seeing higher sales than their predecessors during the same period last year, while the standard iPhone 17 is a major success, performing...
Read Full Article • 523 comments
iOS 26 Feature

iOS 26.1 to iOS 26.4 Will Add These New Features to Your iPhone

Saturday October 18, 2025 11:00 am PDT by
iOS 26 was released last month, but the software train never stops, and iOS 26.1 beta testing is already underway. So far, iOS 26.1 makes both Apple Intelligence and Live Translation on compatible AirPods available in additional languages, and it includes some other minor changes across the Apple Music, Calendar, Photos, Clock, and Safari apps. More features and changes will follow in future ...
Read Full Article • 93 comments
iOS 26

iOS 26.0.2 Update for iPhones Coming Soon

Friday October 17, 2025 7:35 am PDT by
Apple's software engineers continue to internally test iOS 26.0.2, according to MacRumors logs, which have been a reliable indicator of upcoming iOS versions. iOS 26.0.2 will be a minor update that addresses bugs and/or security vulnerabilities, but we do not know any specific details yet. The update will likely be released by the end of next week. Last month, Apple released iOS 26.0.1,...
Read Full Article • 46 comments
HomePod mini and Apple TV

Apple's Next Rumored Products: New HomePod Mini, Apple TV, and More

Thursday October 16, 2025 9:13 am PDT by
Apple on Wednesday updated the 14-inch MacBook Pro, iPad Pro, and Vision Pro with its next-generation M5 chip, but previous rumors have indicated that the company still plans to announce at least a few additional products before the end of the year. The following Apple products have at one point been rumored to be updated in 2025, although it is unclear if the timeframe for any of them has...
Read Full Article • 91 comments
iPhone Siri Glow

Some Apple Employees Have 'Concerns' About iOS 26.4's Revamped Siri

Sunday October 19, 2025 7:39 am PDT by
iOS 26.4 is expected to introduce a revamped version of Siri powered by Apple Intelligence, but not everyone is satisfied with how well it works. In his Power On newsletter today, Bloomberg's Mark Gurman said some of Apple's software engineers have "concerns" about the overhauled Siri's performance. However, he did not provide any specific details about the shortcomings. iOS 26.4 will...
Read Full Article • 318 comments
14 inch MacBook Pro Keyboard

New 14-Inch MacBook Pro Has Two Key Upgrades Beyond the M5 Chip

Thursday October 16, 2025 8:31 am PDT by
Apple on Wednesday updated the 14-inch MacBook Pro base model with an M5 chip, and there are two key storage-related upgrades beyond that chip bump. First, Apple says the new 14-inch MacBook Pro offers up to 2× faster SSD performance than the equivalent previous-generation model, so read and write speeds should get a significant boost. Apple says it is using "the latest storage technology," ...
Read Full Article • 64 comments
Apple iPad Pro hero M5

New iPad Pro Has Six Key Upgrades Beyond M5 Chip

Saturday October 18, 2025 10:57 am PDT by
While the new iPad Pro's headline feature is the M5 chip, the device has some other changes, including N1 and C1X chips, faster storage speeds, and more. With the M5 chip, the new iPad Pro has up to a 20% faster CPU and up to a 40% faster GPU compared to the previous model with the M4 chip, according to Geekbench 6 results. Keep in mind that 256GB and 512GB configurations have a 9-core CPU,...
Read Full Article • 88 comments
m4 macbook air blue

M5 MacBook Air Coming Spring 2026 With M5 Mac Studio and Mac Mini in Development

Thursday October 16, 2025 3:57 pm PDT by
Apple plans to launch MacBook Air models equipped with the new M5 chip in spring 2026, according to Bloomberg's Mark Gurman. Apple is also working on M5 Pro and M5 Max MacBook Pro models that will come early in the year. Neither the MacBook Pro models nor the MacBook Air models are expected to get design changes, with Apple focusing on simple chip upgrades. In the case of the MacBook Pro, a m...
Read Full Article • 116 comments
14 inch MacBook Pro Keyboard

M5 Chip Achieves Impressive Feat in 14-Inch MacBook Pro Speed Test

Friday October 17, 2025 7:10 am PDT by
The first alleged benchmark result for the M5 chip in the new 14-inch MacBook Pro has surfaced, allowing for some performance comparisons. Based on a single unconfirmed result uploaded to the Geekbench 6 database today, the M5 chip has pulled off an impressive feat. Specifically, the chip achieved a score of 4,263 for single-core CPU performance, which is the highest single-core score that...
Read Full Article • 134 comments

Top Rated Comments

TimUSCA Avatar
TimUSCA
89 months ago
Is this going to fix my green-bubble messages constantly saying "Number changed to Primary"? It does this for every single message that comes through, and it drives me nuts.
Score: 9 Votes (Like | Disagree)
BeyondtheTech Avatar
BeyondtheTech
89 months ago
I'm not seeing the benefit of using an eSIM unless using 2 lines. Am I missing anything?
Here's a potential cool thing - your telephone number is embedded in the iPhone. In the event that someone steals it or you lose it, even if they wipe it out and try to reactivate it, it will automatically reactivate the internal SIM and possibly ping its location.
Score: 7 Votes (Like | Disagree)
cableguy84 Avatar
cableguy84
89 months ago
Battery life great after this update, getting over 1 whole day on a full charge now.
Score: 5 Votes (Like | Disagree)
dmccombs Avatar
dmccombs
89 months ago
There are those who have heard that 12.1 also has bugs and were encouraged not to update. It's like that practically with every update for years and years now (and not even just when it comes to iOS).
I was just kidding about the Apple "It Just Works". LOL, those days are long gone. Now its more like "Stand on one foot while chanting, deinstall and reinstall all devices, hard reboot, soft reboot, then hope it kinda works a little".

Seriously, I spend more time re-syncing devices, re-installing, etc. Trying to get my Apple Watch, Phone, iCloud, Pictures, etc to keep working together, is like a second job... OK, ending rant...

Regarding this update, obviously Apple must consider it a bit of an Emergency, yet they don't tell much in the release notes. Ok, I better stop before I start a rant about Apple's lack of disclosure on problems/issues.
Score: 5 Votes (Like | Disagree)
The Oak Avatar
The Oak
89 months ago
Battery life great after this update, getting over 1 whole day on a full charge now.
The update just got out???
Score: 4 Votes (Like | Disagree)
C DM Avatar
C DM
89 months ago
since applying the update 3 days ago.
Sounds like we might be talking about a different update given that this one was just released less than a day ago.
Score: 3 Votes (Like | Disagree)
Read All Comments