This series, which provides a weekly summary of developments concerning low-cost SIMs, SIM-free smartphones, and more, along with a price list of major low-cost SIMs, reported last week that the latest iOS version, "iOS 27," has begun rolling out. MVNOs have confirmed compatibility with low-cost SIMs, and no major issues are anticipated.
The Latest iOS Version, "iOS 27," Begins Distribution; Low-Cost SIM Operation Appears Fundamentally Identical to iOS 26
Ahead of the iPhone 18 Pro launch, the latest iOS version, "iOS 27," has started rolling out. Compatible devices include the iPhone 11, 2nd generation iPhone SE, and later models. This is consistent with iOS 26, meaning that iPhones capable of running iOS 26 can also use iOS 27.
MVNOs have also announced their compatibility status with iOS 27. According to IIJmio and mineo, no issues have been reported so far. It appears that compatibility is fundamentally the same as with iOS 26, with no problems.
Furthermore, starting with the previous iPhone 16 series, all iPhones sold in Japan are now eSIM-only. Consequently, using a low-cost SIM naturally requires eSIM compatibility. While the four major carriers, their sub-brands, and online plans support migration from physical SIM to eSIM and even transfers between iPhones, MVNOs generally require a specific procedure. If this is your first time using an eSIM-only iPhone, please visit the website of your contracted service to confirm the necessary steps.
