Overview
- On Monday Apple seeded fourth developer betas for iOS 27, iPadOS 27, macOS 27, tvOS 27, watchOS 27, visionOS 27 and HomePod 27 to continue iterative testing of Siri AI, performance fixes and UI tweaks.
- Apple simultaneously released release candidate builds for iOS 26.6 and companion 26.x updates, which the company says optimize the Spotlight index so devices are preindexed ahead of the iOS 27 public launch.
- iOS 27 centers on a rebuilt Siri AI powered by Apple Foundation Models with some advanced functions limited to newer, higher‑capacity hardware and subject to regional rules that may restrict availability.
- Beta 4 adds incremental fixes and interface refinements such as a Liquid Glass transparency slider on macOS, standardized rounded corners, enhanced Siri voice controls, a redesigned Podcasts app on Apple TV and watchOS app/grid changes.
- Developers and testers should use secondary devices because RCs are treated as near‑final builds while Spotlight indexing may run in the background now to reduce long reindexing when iOS 27 ships this fall.