https://www.theguardian.com/world/2020/sep/24/take-up-of-nhs-contact-tracing-app-could-be-only-10

Pilot studies show low download rate as app launches in England and Wales

Take-up of the NHS Covid contact-tracing app being launched in England and Wales on Thursday – and once touted as key to controlling the pandemic – could be as low as 10% in some places, government sources believe.