Back in my dating days (well over a decade ago, now), I wondered about a mobile phone-based dating application that would use Bluetooth to identify potential matches in your immediate locality; I suppose it would look a little like a mash-up between OKCupid!, Tinder, and, er... the various Covid Exposure apps we saw emerge in 2020. I fairly quickly came to the conclusion that the obvious safety concerns would probably mean that the expected userbase would be very unbalanced in favour of men. Maybe it would be possible to design something that actually was very safe, but the lessons of the Covid apps suggest it probably wouldn't be possible to get it right first time, and thereafter the stink would linger even when the safety issues were fixed.