Towards the end of March, researchers in the UK and US working with health firm ZOE released the COVID-19 Symptom Tracker app for Android and iOS. In the UK where the app initially launched, the first calculations of symptomatic COVID-19 cases in each area around the country have been published. Staggeringly, the results show up to 9% of respondents in each area may have coronavirus symptoms.

In Birmingham, the UK’s second-biggest city, 6.2% of the 14,124 contributors are believed, by researchers at King’s College London, to be showing symptoms of COVID-19. It's unclear whether this percentage can be applied to Birmingham as a whole, which has 1.1 million residents, in order to come up with the true number of those infected or whether it'd need adjusting.

.@timspector has helped set up an innovative app that allows people to self-report their symptoms -- and it's already providing some invaluable clues into COVID-19. pic.twitter.com/YMBz0MHwxO — Christiane Amanpour (@camanpour) April 2, 2020

A researcher behind the app, speaking to CNN a few days ago, said the app was like a type of radar. In data published on April 1, the researchers revealed that of those who had done a coronavirus test and had tested positive, 59% had reported losing their sense of smell or taste, making it a very good indicator of whether or not you have the disease.

Commenting on the findings, lead researcher Professor Tim Spector from King’s College London, said:

“What we are sharing today are just preliminary results from the two million people who are tracking their symptoms daily. … With so many across the country potentially infectious we have to rethink our policy of testing everyone and come up with other methods to rapidly understand the state of every part of our country. … It is clear levels of infection are very different around the country. We would like to thank every single person who is already participating, and would urge everyone else to download the app and check in every day, whether you are experiencing any symptoms or feeling fine.”

As time goes on and more users download the app, the results that the researchers can work with will become more accurate and may open up new methods to stemming transmission and ultimately help in getting the country back to normal. Presumably, researchers will publish similar data for the United States in the coming days and weeks. If you’d like to download the app, just head over to the project’s homepage and press the appropriate download button.