I have some criticisms of this app. The first one is a big one for me. The app lists ever album I've created in my Photos library. The vast majority of them contain zero panoramas so I have to scroll and scroll and scroll to find a panorama I want to view. The most useful album, the Panoramas album that is built into the Photos app, is not displayed. The second most useful album, the All Photos album is at the very bottom of the list.
Second, there are a bunch of panoramas missing from the list, including the one I shot today using Pano mode with the iOS camera app
Third, it scans my entire photo set everytime it starts up so I have to wait for this operation to complete before I can use the app.
Last, there is no import option.