Koronavilkku – the world’s most downloaded coronavirus app

Solita case Koronavilkku – the world's most downloaded coronavirus app

Koronavilkku was created to help break coronavirus infection chains, and an ambitious goal was set for the app: one million downloads in the first month. This goal was surpassed on the first day, and 2.5 million Finns have downloaded the app to date.

Koronavilkku, developed in two months, is a milestone in our history of mobile apps. The primary design drivers were clarity, reliability, accessibility and security. The app’s high adoption rate, Finnish expertise and community spirit have attracted the world’s attention.

COVID-19 rages across the world – how can we use technology to break infection chains?

The world woke up to the COVID-19 pandemic in spring 2020. The virus infected millions and its symptoms killed hundreds of thousands. By summer, the virus had caused 300 deaths in Finland as well.

How to break the infection chains? How to communicate information to citizens clearly while protecting their privacy? How to guide exposed individuals to contact healthcare services? To answer these questions, a public call for tenders was organised for a national mobile app that could help break infection chains.

The app had to pass the Finnish National Cyber Security Centre’s information security evaluation and meet the accessibility and clarity requirements set for public digital services. Furthermore, the app had to be integrated with multiple background and national health service systems, which made for a demanding technical implementation and schedule.

Solita’s tender for app development was declared the winner in June. Created on an intensive schedule in the midst of a pandemic and Finland’s traditional summer holiday season, Koronavilkku was released a mere two months later on August 31st 2020.

Solita Koronavilkku app

International standards guarantee privacy protection and compatibility in Europe

Firm objectives were set for service design: security, clarity, accessibility and project transparency. An ambitious goal of one million downloads in the first month was also set.

During the design process, the team listened closely to the comments and experiences of both healthcare professionals and citizens. Careful attention was also paid to building trust through active communication and broad collaboration between the different parties. The app could only be successful by winning the trust of ordinary Finns and healthcare operators alike.

How Koronavilkku works

Koronavilkku anonymously keeps track of the phones encountered by the user that have the Koronavilkku app or another compatible European coronavirus app installed.

Each phone is assigned a randomised identification code that changes multiple times a day for enhanced privacy protection.

The phones that come into close range of each other exchange these codes over Bluetooth. This works even if the phone is locked or the Koronavilkku app is closed.

If the user has encountered someone who later reports an infection via the app, the user is notified of potential exposure. The notification includes instructions of what to do and the option to contact healthcare services. If the user is found to be infected, they can report their infection anonymously to warn other app users.

The implementation was based on international standards and a decentralised model where there is no centralised place that collects users’ information. In this model, infection chains are identified based on pseudonymised identifiers that cannot be used to identify users. These design choices provide the best privacy protection possible.

Open communication and activating the Finnish community spirit were also at the core of the strategy. It was decided early on in the development process to publish the app as open source code, so that both enthusiasts and information security professionals could verify its security. The record-breaking download numbers were aided by openness, transparency and ample positive visibility in the media. A persistent effort was made on social media to answer the hundreds of questions citizens asked.

A milestone in the history of Finnish mobile apps

Koronavilkku has met people’s expectations: it is easy to install and use while being secure. The focus on intelligibility and security was a success, as the app has received high praise from Finnish users.

Today, about half of Finland’s population have downloaded Koronavilkku onto their mobile device. Koronavilkku has a top adoption rate in Europe relative to the population and it has raised interest around the world: for example dozens of international media outlets have written articles about it

Koronavilkku is a milestone in the history of Finnish mobile apps and a concrete example of how technology can be used to prevent the spread of disease and enhance the communication of information. The app has helped break infection chains and save Finnish lives in the midst of a worldwide pandemic. Its high adoption rate and the Finnish community spirit have attracted interest across the world.