If you are asking, it would be interesting to hear their opinion on both built-in avionics (e.g. Garmin G3x, GNC, GTX) and portable avionics (e.g. Stratus, EFB).
I will have to assume that in the "certified world", both firmware and database updates are logged for all built-in avionics. As I understand it, if database and/or firmware updates have not been applied to the crew's EFBs, the plane cannot push back; thus, I believe that EFB updates (both firmware and database) are also logged, but just not in the aircraft logs.