The UK Government’s test and trace app has been back in the news in the last week following the admission of Dido Harding that she had been asked to self-isolate by the very app she was charged with creating. The BBC ran the story here, following Harding’s original tweet, stating there was ‘Nothing like personal experience of your own products’.

My first brush with Harding’s product came on 31st October when I received a similar notification. In my case it advised 10 days isolation, so I cancelled lunch with my friends and settled down into a long stretch at home. (Of course, this only got longer but I was not to know at that time).

Getting ‘pinged’

There is nothing like getting a notification like this to make you research exactly why you have got it. Digging into the app’s FAQs it seemed that I had been less than two metres away from someone for at least 15 minutes, who had later tested positive for COVID. The app uses Bluetooth Low Energy (LE) to do this (seasoned technology experts might like to look away now). But Bluetooth LE has a reported range of up to 100 metres, so how is the phone interpreting how close I am to someone with the accuracy of two metres? Bluetooth LE also powers my smart watch and, as often as not, I have to reboot my phone to get the two to connect – despite the app that supports this being from one of the biggest fitness tech companies in the world.

10 days not 14

Something that initially confused me was the need to isolate for 10 days not 14. It emerged that my last contact with the now infested person was four days before the app informed me. On one hand this is entirely reasonable: the infested person had to get ill, get a COVID test, test positive and report this to the app before I was informed. If anything, four days was quite a short time for that to happen. However being this specific about the date meant I had a pretty strong chance of working out where I was when this contact took place and who it was with.

At the time, my wife and I were in Bristol for a couple of days. Only one of us checked into each place we went to, so by deduction I could be pretty sure that I was in a restaurant when the contact happened. The privacy of this element of the app is potentially a little compromised. Incidentally, my wife did not receive the alert but did the right thing and isolated anyway.

Contact tracing

Finally, you may have missed one critical element of the app – switching off contact tracing. I was oblivious to this when I downloaded and only today have discovered the true reason. You are actively encouraged to switch off contact trading when you are in protective clothing or in a safe environment where might be in range of someone but not in contact. So I should have switched the app off when in a hotel room where the occupants above, below and to each side could have potentially been within two metres. I had no idea of this and had left this element on. In fact, bearing in mind I had no ill effects in the 10 days, perhaps this is the most likely outcome.

It’s not easy rushing to respond to a health crisis and, when the app finally arrived, it was downloaded by millions, in a demonstration of the public’s desire to help. While the app seems fit for purpose, I wonder if enough attention has been paid to telling people about the features and how to use it most effectively. It reminds me again that the tech can be world class but it will only ever be as good as the interaction with the people using it.