Coronavirus: Tracking app aims for one million downloads

An app that tracks the symptoms of Covid-19 in the UK has become one of the most popular downloads.

Its creators aim to deliver insights into why some people get the disease more severely than others.

They also hope to create a map showing where outbreaks are happening, and help distinguish cases from those of the common cold.

It is one of many such new apps. Experts have warned people to be cautious about which they download.

At present, Covid Symptom Tracker is the third-most popular app in Apple’s UK store and second in Google Play’s new releases chart for the country.

Its developers are targeting one million downloads in 24 hours.

The program has been shared thousands of times via WhatsApp and other social media platforms.

Created in just three days, it has already reached 750,000 downloads, and according to its developers is being installed at a rate of 50,000 times an hour.

It was created by researchers at Guy’s & St Thomas’ hospitals and King’s College London university, in conjunction with the nutrition advice start-up Zoe.

The app was the brainchild of Prof Tim Spector, a genetic epidemiologist at King’s College, who has specialised in the genetics and medical histories of twins for the past 25 years.

“I was rather depressed as they were shutting down everything in the university, and I thought that twins are the best studied people in the country so how can we use that information in this crisis?” he told the BBC.

Initially the app was only made available to the twins who were taking part in his studies, who were sent a home-testing kit to better understand which symptoms corresponded to the coronavirus infection.

But the professor realised it could be scaled up to the general public, without the testing element.

“The NHS hasn’t come up with a better alternative and this app seems to be working. We are hoping to get to one million downloads by the end of the day and we will also be ready to release data by then for the NHS, data modellers and researchers to play with,” he said.

The software requires users to share personal details, including their age, height and medical history. It asks people to describe symptoms, if they have any, on a daily basis as well as to give a temperature reading.

Prof Spector said it could potentially help the NHS:

• learn how fast the virus is spreading in a particular area, as well as highlighting high-risk parts of the country
• better understand the symptoms, including the differences between those of the virus and the common cold
• explain why some people develop a mild illness while others become critically unwell

A spokeswoman for Zoe told the BBC that all shared data would be anonymised, and that no data shared in the app would be used for any commercial purpose. She added that users could delete all their records when the crisis was over.