iOS 27 updates cause temporary battery drain and device heat due to background indexing processes, particularly for Siri AI re-indexing, which may last several days. Performance returns to normal once setup completes, potentially with improved battery efficiency.
Apple released macOS Tahoe 26.7 and macOS Sequoia 15.8 alongside macOS 27 Golden Gate, featuring important security fixes recommended for all users. The updates include WebKit vulnerability patches, though full security details have not yet been published.