BUG! iOS version of Lightroom Mobile did not save photos shot in the Adobe app! Settings: HDR, grid lines enabled.
I am not a newbie. I have subscribed and used routinely "Lightroom Classic" (Ugh! just hate that name) for many years. Shoot a full frame camera. While I don't chimp, I was watching my iPhone 6S+ screen 'flash' with each shutter press. In the same session (along California coast), shot with the native iPhone app, all photos stored normally.