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#WirVsVirus Hackathon

let's dev participates in the hackathon of the federal government

Hackaton teaser
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let's dev at the #WirVsVirus Hackathon

The #WeVsVirus hackathon aims to develop and inform digital solutions for people in the current situation. The hackathon took place online from March 20 to March 22, 2020. In the process, challenges were first collected in different categories and selected by participants. Then it was time to create the prototypes, which were then presented on Sunday. A digital support program will now help to realize these solutions.

By implementing the idea we have developed, we would like to do our part to improve the current situation. Our team is composed of our UX designers and developers and developed a finished prototype of our app idea at the hackathon.

Our app idea for the hackathon

App Mockup
Hackathon App icon

CO Scan

Prevention through location!

Technology Stack

LOVE, iOS, Swift, Objective-C, Java, HTML5, CSS3, JavaScript, Spring Boot, Rest, MySQL, Tomcat, Docker, let’s push

3rd Party applications und services

let’s Push (Push service for bulk sending of push notifications)


The COVID-19 crisis imposes severe restrictions on society and at the same time creates massive uncertainty. The risk of virus spread and infection is enormous, and the incubation period can be up to 14 days. Until recently, people gathered in public transport, institutions, restaurants, playgrounds or supermarkets without knowing if there was a person infected in the immediate vicinity. Even despite Social Distancing, this is still the case on unavoidable contact occasions. The symptoms of COVID-19 are not yet fully understood, and citizens lack important experience in dealing with the disease. The consequences of not isolating early and as a precaution are underestimated. That is why the desire for freedom of movement coupled with a lack of awareness of the dangers is also the main reason for the continued rapid spread of the virus.

User Stories

In a pandemic situation, I would like to know if there is a probability that I have been in contact with an infected person. This refers not only to the immediate environment that I know personally, but also to other localities, such as restaurants. I would like to be transparent about whether others present were infected with COVID-19 at the time I was there, so that I can take the necessary precautions to protect myself and those around me, as well as to contain the spread of the virus.

I am not really interested in who, but only in whether someone was infected. Because of the incubation period, this information is relevant for me in relation to all locations visited in the past 14 days. Only in this way, in conjunction with knowledge of common symptoms, can I draw the right conclusions and make target-oriented decisions.

Ideally, this is done through an app in which I specify a location myself and am notified via push messages as soon as a person infected with COVID-19 has been at that location in the same time frame. in the same time frame. Self-diagnosis helps me determine if I am experiencing COVID-19 symptoms and should visit a Testing Station or should see a doctor. If I have been infected myself, I can share this information anonymously through the app so that others who were at the same location as me at the same time can be location at the same time will be informed.

Functions at a glance

Enter positions

Register positionsn

The first function of the app is the tracking of locations outside of the home walls. This allows you to anonymously record your position in any public place. The date, place and time of the location are stored for 14 days. The GEO data is tracked once, not the way there or how long you stay there. If a user tests positive for the virus, he or she stores this information. In this way, users be notified if they have been to the same place within a certain period of time.

Enter positions
Symptom diary and test results

Symptom diary and test results

The second feature of the app offers users the ability to check off acute signs of illness listed in a symptom diary or enter their own. The app makes a risk assessment and provides recommendations, such as a COVID-19 test. A positive test result is entered into the app.

Push Notifications

Push Notifications

By means of push notifications, the app informs users about possible contacts to ill persons. In the settings, users can choose how often and in what way they want to receive messages on their smartphone. The technology let's push which we develop, is integrated in the process.

Push Notifications

How did the project come about?

The idea

The original idea for the project came from our CTO Christian. He has been observing the situation around COVID-19 for a long time and thought about how he and we as a company from the tech industry can make a social contribution with software in these times. In joint discussions we pushed the idea and defined the scope for the #WirVsVirus hackathon.

Our magical project team

This was our eleven:

Maren (Privacy)

Karl (Sponsor)

Aileen (UX Design)

Julian (UX Design)

Arne (App development)

Fabian (App development)

Sebastian (App development)

Martin (Build Engineering)

Christian (Project management)

Tim (Backend development)

Tobias (Backend development)

In addition to the motivated colleagues from let's dev GmbH & Co. KG we could welcome Maren from VELIT Consulting GmbH & Co. KG and Tim from Berlin.

What's next

The prototype developed is functional, the people behind it experienced and highly motivated! Should the opportunity arise to further develop the application, we are very interested in participating. By using cloud technologies, the application would be easily scalable. The mass sending of notifications is mapped via an already established and proven service.

Vote now!

Which hackathon challenges will be further developed will be decided by a jury and additionally in a public voting. Each project idea will be presented on a DevPost-Seite and in a Video on YouTube. From Monday, March 23, 2020, public voting will start there. The likes (positive ratings) of the YouTube video will count.

Please vote for our video here:
CO Scan App on YouTube

Voting ends on Thursday 26 March 2020 at 22:00. The final results are expected to be published on Sunday, March 29, 2020. We are super excited and look forward to positive reviews!


WirvsVirus, our TEAM, Pizza supplier, Coffeedealer, let's dev GmbH & Co. KG, VELIT Consulting GmbH & Co. KG, let’s Push and all supporters out there.

Hackathon #WirVsVirus

The #WeVsVirus online hackathon creates a digital space where solutions to emerging challenges can be developed, tested and improved together. The prototypes developed in the 48-hour hackathon will then be implemented in a digital support program to better address challenges during a situation such as the current one with COVID-19.

TAnyone can participate. Whether as a participant, as a sponsor by making a suggestion for a challenge, as a mentor or as a support for post-implementation support: everyone can do their part to emerge strengthened from the current difficult situation.

In #WirVsVirus, an incredible 42,968 participants, 1,924 idea generators and 2,922 mentors together implemented over 1500 projects.

More about the #WirVsVirus Hackathon