Talking about 5G in Android, Google suggest to make use of the improved bandwidth on UX by replacing images with videos ( AR centric ), prefetch content than let it buffer, give importance to streaming, assume that all those bandwidth heavy games and activities can be done outdoor too.
Google says
We’ve been hard at work building in support for 5G on Android, and have been working with 5G carriers starting with Verizon and AT&T in the U.S., as well as others in Europe and Asia to provide necessary Android features for app developers looking to build 5G experiences.
Google has a dedicated 5G page for Android where you can find official documentation and resources.