I spent a Sunday in Paris with a friend, Jason Boone, who's made a video about Adobe Rush and what makes it such a good video editing tool. It has been presented as being easy, syncs over Adobe Creative Cloud and has a lot built in to make you a more productive editor. This video shows whether that's true.
You can download the mobile app for iOS, and early in 2019, the Android version will be released. If you subscribe to the Creative Cloud, you'll get the mobile and desktop app included, and what Adobe tried to achieve here, is the ability to sync what is shot and edited on mobile with the desktop app, and if need be, to export to Premiere Pro for final edits.
The Mobile App
The touch interface on the mobile app is quite intuitive and cutting and moving shots around is easy to do. Adding text, music, and using color profiles to give your video that professional feel is all done on the iPhone and it makes it a pleasure to use.
We used my iPhone X, the Moment Wide Angle lens, and adapter and the GoPro Hero 7 Black for some hyper-lapses, and had a good time shooting. It was possible to get the shots off the GoPro directly onto the phone and import it into Rush. I can't tell you what the differences in frame rates were, but it doesn't look as though it was a problem.
What I Think Adobe Can Improve On
I think the syncing with Creative Cloud is an issue. It's super slow and the mobile app shows it has synced when it hasn't, so an indicator showing progress will be a great update I am sure they're working on. You have the option to sync via Dropbox or Google Drive, which seems to work much faster. Other than that, the interface seems to be moving in the right direction.
Conclusion
If you're a stills photographer wanting to document your way of working and the environment you find yourself in using your iPhone, Rush can be useful. If you are spending a lot of time at airports or on flights, this will be a more comfortable way to work instead of getting out the laptop. It's the first release of Rush, so it can only get better from here on moving forward.