Today, Apple released the eighth developer betas of the next major updates to its operating systems, including iOS 11, macOS 10.13 High Sierra, watchOS 4, and tvOS 11. The company has been seeding new builds weekly since beta 5 was released, and this is likely to be the last one before the GM seed is offered following the iPhone 8 launch on September 12.
Because of this, there obviously aren't a lot of changes in this build; instead, it focuses on fixes. iOS 11 still has some problems with third-party apps like Audiobus 3, MobileIron Mobile@Work, Tweetbot, and Square Cash, but at this point, it's likely the developers' responsibility to get them working.
macOS 10.13 High Sierra has fixed most issues that have to do with the new Apple File System (APFS), but it still isn't supported by HDD-only Macs or iMacs with 3TB Fusion drives with BootCamp. Also, some third-party apps might not recognize an APFS volume, and again, it's unclear if Apple plans to fix any of this in time for the GM.
watchOS 4 beta 8 contains a known issue where workout sessions may be slow to start, and they may not update with calorie and distance measurements. tvOS 11 still has some issues with Sling TV and FoxNow, but that's about it, since there aren't many new features coming to tvOS at all.
To be clear, these are near-final builds, and beta testers will see the finalized versions in a couple of weeks.