It was an ID10T error. I assumed the app was upgraded automatically since the screen looked very different. Turns out something was in a messed up state. Rebooting the phone brought everything back to looking normal and the formerly blank database display was back to normal.

Doh

Yesterday I had a pretty full databaase, today I run it, the UI has changed, although I didn't update anything. Database has been cleared to 0 entries.
What happened and is the data still available some place? Did not have a chance to upload.