Apple has expanded Siri AI voice customization in the fifth beta of iOS 27, giving users more control over how Siri sounds across a wider selection of American and British voices. Don’t miss the best of The Mac Observer Set us as a preferred source and our Apple reporting ranks higher in your Google Search results and Discover feed — one tap, no account changes. On iPhone, Siri AI voice customization works with the iPhone 17 Pro, iPhone 17 Pro Max, and iPhone Air.