SchoolOrganizer is an app where you can manage your timetable, homework, exams, grades and more. I developed this app while I went still to school. Since then I brought the app further and now it supports iPhone, iPad and Apple Watch. The app helps student around the work, but mainly in Germany, to get through their school days every day.
As the development started over 5 years ago the first version was developed with Objective-C and UIKit. Since then I upgraded the app to Swift and since a couple of months some parts already to SwiftUI.

Git Activity is an app that lets you track your activities on Git platforms like GitHub or GitLab. It reminds you to contribute something today even if it’s just a small piece.
The app is fully developed in SwiftUI and is currently available for iPhone and iPad. The key part of the implementation is a shared Swift package that holds the different Git APIs and is used by the app as well as the Server-Side-Swift system build with Vapor. As the app can talk to the Git providers in the same way as the backend which only providers upgraded push notification support this code sharing reduces code duplication and the same algorithms on all platforms.

Reaction speed is a small game that tests a users reaction and sense for timing. The user has to a tap exactly every 2 seconds. This game has already been played by thousands of users worldwide and with the Game Center implementation users can challenge themself.
I developed this app after seeing similar gameplay at a real-world event where you have to hit a button after an exact amount of time. This app taught me a lot about Game Center development and in a rebranding in 2020 I used a lot of experience about ASO that I gathered over the years.

I love GraphQL and Server-Side-Swift. So when I researched these technologies for a project I couldn't find a good solution. I created a package that can combine an existing GraphQL implementation in Swift with the popular server framework Vapor. The results are multiple packages that make the implementation of GraphQL servers with Swift easier and ready to use, even production.

MomentMap is a social network where people can spontaneously share their experiences with the world. The team started to form in 2014 and we founded the first company in 2014. With a team of people of various expertise like business development, marketing, sales and software developing we developed a platform for sharing user content. As this was our first startup and working on this in our free time we see this as a learning project.
Developing MomentMap helped me to learn what it means to work in an agile team. We also encountered various problems in our development process we successfully solved and got experience from that we can apply in future products.
Part of the MomentMap product we open-sourced our backend for transforming GPS coordinates into location names. This is built on top of OpenStreetMap data that is stored in a PostgreSQL database and a Vapor Rest server that is optimized for speed.