In almost 30 years working in software development, I have been involved in many projects. Many of them as a freelancer for companies and start-ups in Germany, Switzerland, Great Britain, Canada and the USA. I would like to briefly introduce a few of them here.

iOS Software

COI - Chat Over IMAP

The OX COI Messenger is a mail-based chat app. This app provides the user interface for an IMAP / SMTP based chat on Android and iOS.

This is a Flutter project that I really wanted to work on and even gave up my freelance work for. But that's another story...

The project was discontinued by my former employer and is now on freeze. It is not being actively developed at the moment.

GitHub Projekt


Mimo - Learn to program on your iPhone - whenever and wherever you have time! With hundreds of playful and interactive micro-lessons, computer science has never been so easy and fun.

For Mimo, I worked on almost every part of this app and wrote the core from scratch.

App Store


The Zumtobel IB-Tool is the perfect tool for basic commissioning of your lighting solution. It enables simple, wireless addressing of all LUXMATE outlets in the building and assignment of control devices to the outlets....

The entire system can be checked for functionality and correct installation at the touch of a button. The tool also offers the option of operating all actuators and permanently saving their scene settings.

App Store


Order your food simply by smartphone and choose from over 700 delivery services in Austria. With Mjam you'll always find the right thing. Enter your postcode or use your current location, create your favourite menu and order easily.

I was one of two developers and worked on almost every aspect of this app.

App Store


riskmethods GmbH - offers a SaaS, cloud-based supply chain risk management solution. The company focuses primarily on SMEs and large companies in all industries that buy internationally.

For this Swift project, I worked on several parts of their iOS (iPhone and iPad) and tvOS app.

App Store

Sir Apfelot

Sir Apfelot delivers the exciting, informative and helpful articles of the blog clearly arranged and easy to use to your iPhone! Since 2012, the blog has been offering new articles from the world of Apple and technology on an almost daily basis.

I was the sole developer of this app. It was written from scratch using Swift and the Realm database for local persistence.

App Store

macOS Software


With Podlive for iOS, macOS and tvOS you can listen to live streamed podcasts. We currently support all podcast live streams that are uusing Ultraschall with Studio Link OnAir. You can mark your favourite channels to be notified immediately when a channel starts streaming via Apple's built-in push notifications.

Podlive is an open source project, the source code is available on GitHub.

Mac Spp Store

Review Times

Review Times was a small application that places an icon in the menu bar. Clicking on the icon displays a popover with the calculated review times for both the Mac App Store and the iOS App Store. All data is retrieved from

This software is no longer being developed.