https://wccftech.com/heres-how-ios-15-4-stacks-up-against-ios-15-3-1-in-a-speet-test-comparison/ > Apple recently released iOS 15.4 to the general public with a boatload of new forward-facing features. The update brings features like Face ID with a mask, new emojis, ProMotion enhancements, and a lot more. However, we have to take note that some updates slow down your iPhone. If you have not yet updated to iOS 15.4 and want to see if the update will take a hit on performance, you can check out the speed test comparison. > As mentioned earlier, sometimes iOS updates slow down the performance of iPhones and it is vital to keep a check. If you have already updated to the platform, the new iOS 15.4 speed test comparison against iOS 15.3.1 will let you know if the device features the same level of performance, improved, or slowed down. You can also check out the video below for more details.