"Simplicity is the ultimate sophistication."

Leonardo da Vinci

Tech Lead Software Engineer IT Consultant

Hi, my name is Klemens.

I help companies build great apps for Android, iOS and web and make them scalable based on cloud technologies.


creative workline GmbH (Vienna) | 2014 - today

Supporting the success of companies and startups from Austria, Germany and Switzerland by designing and developing mobile app solutions (Android, iOS and PWA/hybrid/Ionic) that users love. We create custom high quality app solutions starting from consulting as part of a conceptual and architectural phase, moving on to UI/UX design, agile development, deployment, operation and maintenance. Apart from apps we also develop web, backend and database solutions that run on cloud based server technologies like AWS, Google Cloud (GCP), or Firebase. Previous clients in the field of app consulting and development include T-Mobile USA, Spar, Österr. Post, City of Vienna, Wunderlist (acquired by Microsoft), among others.


An excerpt of companies in which I was a founder/partner:

uugot.it | Partner & CTO | 2018 - 2022

Learning languages while watching TV: uugot.it enables learning languages while watching TV. The innovative app streams TV channels on smartphones, tablets, and desktop browsers and adds interactive subtitles. In case one doesn't understand a certain word one can click on that word and it will automatically be translated into the language of the user. With uugot.it language learning becomes not just super easy but so much fun as well. 

Toni.ai | Co-founder & CTO | 2017 - 2020

Engaging fans with their favorite sport clubs in one-on-one conversational interfaces. We are creating virtual sports buddies for fans on the popular messaging platforms like Facebook Messenger. With the Toni.ai platform we strive to enable the world’s best sports chatbots and bring messenger marketing for professional sport clubs to the next level. Customers include LAOLA1.at (Sportradar), FC Red Bull Salzburg, spusu LIGA (HLA), among others.


I (co-)founded these groups with, but running them wouldn't be possible without the help of some amazing partners:

AndroidHeads Vienna | Founder & Co-organizer

In 2013 I founded the AndroidHeads Vienna Meetup group with the goal of connecting the Android and mobile app developers community in Vienna. In the meantime the group has grown to over 600 members. We are also co-organizers of the droidcon Vienna conference. AndroidHeads is part of Google's Community Leads Platform and sponsored by JetBrains (the company behind IntelliJ IDEA and Android Studio).


SportsTech Austria | Co-Founder & -organizer

SportsTech Austria is a platform connecting sports enthusiasts, startup visionaries and tech experts to share their vision and levelling up the Austrian SportsTech industry. The meetups have been supported and/or hosted by organizations like SK Rapid Wien, spusu, NEOH, motion4kids, and Talent Garten.



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In today's fast-paced world, people expect instant answers to their questions and immediate solutions to their problems. That's why chatbots have become an indispensable part of mobile apps, and ChatGPT is one of the most advanced language models available in the market today. In this article, I'll guide you through the process of integrating ChatGPT into apps for Android and iOS... Continue reading

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ngx-logger ist eine großartige Logging-Bibliothek für Angular. Sie ähnelt andern Logging-Libraries, die wir von anderen Plattformen wie Apache Log4j (Java), Timber (Android, Kotlin / Java) und Winston (node.js) kennen, ist jedoch nicht so leistungsfähig und funktionsreich wie einige dieser Bibliotheken. Ich weiß, dass Logging-Frameworks ... Continue reading

You can find more articles on the following pages:


For more info about professional experience as a consultant, freelancer and entrepreneur since 2004, education and proficiencies please visit my LinkedIn page. I'm a contributor to Open Source Software (OSS) projects and also active on StackOverflow and GitHub.

Clients I have worked for in PM, leading dev, full stack developer, or consulting role include: Stadt Wien (City of Vienna), T-Mobile USA, PayPal, FC Red Bull Salzburg, LAOLA1/Sportradar, Spar, Österr. Post, Emmi, REWE digital, Wunderlist (acquired by Microsoft), and many others. I have already worked for customers from a wide variety of areas - startups, SMEs, corporate and public sector - primarily from the DACH region (Germany, Austria, Switzerland).

As a startup founder, technical co-founder, CTO, and freelancer I have accompanied the process of digital product development from the idea to ongoing operation many times.

Licenses & certifications

Open Source

My preferred tech stack includes, but is not limited to the following Open Source projects: Android, Angular, Angular Material, Apache, Capacitor, Cordova, Docker, Express, ESLint, Grails, Groovy, IntelliJ, Ionic, Java, Kotlin, lodash, MapBox/MapLibre, moment.js, MongoDB, Mongoose, nginx, RxJs, spaCy, TypeScript, Ubuntu, WordPress, video.js, Visual Studio Code, Swift.

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