Apple's focus on efficiency and performance improvements is good news for older iPhones.

Apple's two main focuses for iOS 27 were polishing the performance of its mobile operating system and adding a sprinkle of AI across everything thanks to Apple Intelligence and Siri AI. Anything AI-related is the most attention-grabbing, but Apple's attempts to clean up its software have already secured a big benefit: the company isn't dropping support for any iPhones this year. That means any iPhone that ran iOS 26, including the seven-year-old iPhone 11, can run iOS 27.

It's not clear if any one change made extending the lifespan of the iPhone 11 possible. The company is promising that apps running in iOS 27 will open up to 30 percent faster, among other speed improvements. The efficiency could have also been unlocked by iOS' CPU scheduler, which Apple also claims has been newly optimized. That said, this doesn't change what iPhones can work with Apple Intelligence as well as the new Siri AI features — the oldest one is the iPhone 15 Pro and Pro Max.

The decision is notable, not just because of the phone's age, but because not all Apple devices were treated the same. For example, watchOS 27 only runs on the Apple Watch Series 10 and up, Apple Watch Ultra 2 and up and the Apple Watch SE 3. That leaves behind three Apple Watch Series models, one Apple Watch SE model and one Apple Watch Ultra model that were able to run watchOS 26.