Technical issues with Bluetooth may have delayed the NHS contact tracing app and triggered a breakdown in communication between the app’s advisory board and the government.
Gus Hosein, a member of the ethics advisory board overseeing the app’s development, described a “frustrating” lack of communication with the government over data resulting from Bluetooth tests.
“I have asked repeatedly for data on how the trials and tests went with Bluetooth data, and they have never shared those results,” he said.
The contact tracing app, which has been pushed by the government as a tool to ease lockdown restrictions, has been built around Bluetooth technology designed to create a “digital handshake” between smartphones to confirm contact with other people.
If someone later develops symptoms of Covid-19 and is found to test positive, an update on the app alerts those who have had close proximity with that person and asks them to self-isolate.
However, signs have emerged that there may be issues with how the app is locating users. A contract released by the Government last week showed the focus of the app’s testing was around “whether the proximity service satisfies the requirements”.
Experts have claimed that the use of Bluetooth technology to track people involves a number of limitations, including a lack of accuracy that could register phones a distance away.
Researchers at Trinity College Dublin have founded that Bluetooth strength can vary in real world situations such as in a supermarket or on a train, where signals could reflect off of metal surfaces and make it difficult to determine if two people should be registered as being in close contact.
“They’re trying to get mobile phones, devices that we have come to rely upon intimately for our work and personal lives, to turn into localised reporting devices, using an old protocol promiscuously,” Mr Hosein said.
“They sold ministers and others on how they were so brilliant at using Bluetooth, never sharing the data on how it was working out… phones were never designed to work this way.”