Apple this week released the Golden Master of iOS 11, watchOS 4.0, and tvOS 11. These penultimate builds mean Apple's yearly updates are nearly done. Devs need to be aware of some important changes to the code base. Further, Apple wants to see some ARKIt augmented reality apps ready by Sept 19.
Google has released the beta version of Android 11. Developer previews for Android 11 have been around since February. Now, Google has officially opened up the beta release with three themes: people, controls, and privacy. Google has canceled the virtual launch event it originally planned for v11.