Boris Johnson’s government has ditched plans to develop a custom-made contact-tracing app in favour of a new model after the rollout was beset with problems. In a major U-turn, ministers announced a switch to technology provided by Apple and Google – abandoning an NHS model that aimed to give the health service greater access to patient data. Officials admitted the app, designed by the health service’s tech arm NHSX, was highly inaccurate, picking up just four per cent of contacts on Apple phones and 75 per cent of contacts on Android handsets. By contrast, the model designed by the tech giants picked up 99 per cent of contacts on both Android and iPhones. The shift raises questions over how much time and money was wasted pursuing a bespoke app that never materialised.