Interesting but limited
Without the ability to choose more than one feed source, you’d better have a good memory because you are not going to get the USGS and European feeds on a single screen. If you don’t want the default feed, you have to select what you want each and every time you launch the app. You can set up “views” that can be saved but not feeds. Hmm.
The whole user interface is clumsy, but that’s more the fault of the Apple TV remote rather than the app.
Need more control over the appearance of the rings and other visual elements.
Fun for a quick look, but nothing more.