With iOS 27, Apple focused on making improvements to iOS performance, optimizing everything from system animations to AirDrop transfer speeds. iPhone performance is smoother and faster on all iPhones able to run iOS 27, which includes the iPhone 11 and newer. There are over 80 iOS 27 improvements Apple announced, with 10 of the most useful listed below. App Launching Apps launch up to 30 percent faster in iOS 27, and that includes Apple's own apps and third-party apps.
The ones that matter to me are: cellular to wifi transitions, and one that isn’t directly mentioned: Messages app launching. Lately, it’s been randomly crashing on load or taking forever to load. An OS reboot temporarily fixes the issue.