iOS 27 is now available for both iPad and iPhone for free by going to Settings, the General section, and then selecting Software Update. The update could take a few minutes to roll out to all iPhone users due to the number of people who will be upgrading.
The revamped Siri is available on iOS 27, a more capable and smarter AI, but you might have to sign up to use the new AI after you update. You can install iOS 27 and iPadOS 27 on devices with the A16 iPad, 6th gen iPad Mini, recent iPad Air, the iPhone 11 or newer, and the iPhone SE 2. To run the new Apple Intelligence features, you will need an iPhone 15 Pro or newer.
The new Apple Intelligence features include Spatial Reframing to change the position of your camera virtually, Extend Tool, where images are expanded, and Clean up for cleaner, high-quality images.
