Coronavirus symptom tracking app downloaded hundreds of thousands of times

An app has been created to allow people to track the symptoms of Covid-19 and help fight the spread of coronavirus.

It has already been downloaded hundreds of thousands of times and has shot to the top of the iPhone App Store, as users rush to catalogue their symptoms.

Importantly, researchers have also asked users to sign up to the app and report how they feel even if they are not showing symptoms. That will give extra information on where the disease is spreading to, and how it affects different people.

All of those individual reports will be gathered together into a data set that will be given to health organisations such as the NHS and research institutions including universities, the developers say.

Researchers hope to use that data to help slow the outbreak by learning how fast the virus spreads, where the highest-risk areas are, and who is most at risk. Tracking symptoms will also help researchers better understand how the symptoms of Covid-19 are linked to underlying health conditions, researchers say.

The app – currently only available in the UK, but launching in the US on Thursday – could help answer important questions about the disease such as why some people develop severe and fatal symptoms while others only experience relatively mild ones. It may also help doctors distinguish between the very similar symptoms of Covid-19 infection and seasonal coughs or colds, and to make it easier for people to better understand what is making them unwell.

The study is open to the public and anyone can download the app for free through the app store. To use it, they must consent to the app's privacy policy, which allows personal health data to be shared with research institutions but commits not to use it for commercial purposes.

The app is created by nutrition company Zoe, which is led by Tim Spector, professor of genetic epidemiology at King’s College London. Zoe began at King's before being launched as a private company, and researchers from the university and other organisations helped to create the app.

It will also make use of data and participants from the TwinsUK study, which has profiled 15,000 identical and non-identical twins over three decades in an attempt to gather important medical information. Twins that are part of that study will be able to record information about their health, and if they show symptoms of Covid-19 will be sent a testing kit that will allow for better understanding of symptoms.

“These are worrying times for everyone," said Professor Spector. "Our twins are fantastically committed, enthusiastic health research participants who have already been studied in unprecedented detail, putting us in a unique position to provide vital answers to support the global fight against COVID-19. The more of the public that also use the app, the better the real-time data we will have to combat the outbreak in this country.”

Members of the public that participate through the app will not have access to the home testing part of the study.​

The app is available on the Apple and Google app stores in the UK now. It is coming to the US on 26 March, Zoe said.

The success of the app comes as the NHS launched its own app intended to allow volunteers to sign up and help the NHS, which has already seen more than 170,000 people sign up.