Assessing the #security of computer systems is really hard because of "known unknowns" and "unknown unknowns". For example, there are lots of reports about #NSO #Pegasus being found on #iPhone but few about #Android. One might be tempted to conclude that Android is more secure. The truth is unfortunately much harder to pin down. For example, it is harder to detect and confirm Pegasus on Android, although it is clear that there have been plenty of infections on both platforms.