@CliftonR Thank you for the thought but we're using a particular system. We didn't create our own prefs/persistence format, we're using an Android feature called "Rooms". It's basically managing an sql database for us, changing "file formats" means running some sql ALTER TABLEs, and upgrade means running the registered ALTERs in a particular order (and Android decides which upgrade SQLs to run). So to improve things we'll have to work within this system.