The first release of Android Go Edition, based on 8.1 Oreo, was... not great. On the plus side, that means there's lots of room for improvement. Google today announced the next major release, named "Android 9 Pie (Go edition)," with storage improvements as the highlight feature.
The update obviously includes everything added in Pie, like gesture navigation, updated emoji, adaptive brightness, a new app switcher, and various UI improvements. The main Go-specific improvement is a reduction in reserved storage; Google says Pie Go Edition is "up to" 500 MB smaller than the Oreo version. On budget phones with 8GB or less of internal storage, every MB counts.
There's also "[an] accessible dashboard for tracking and monitoring data consumption," but Google didn't specify how it's different than the app usage data that has been in stock Android for years. The first devices with Android Pie Go Edition should arrive this fall.