Presented by:

Bachelor technical mathematics, Graz University of Technology in Austria Master Industrial Mathematics, Graz University of Technology in Austria Since 2019 Institute of Software Technology, Graz University of Technology in Austria

Vesna Krnjic

from Catrobat - Graz University of Technology

Vesna Krnjic has a PhD in Computer Science from Graz University of Technology where she is also now working as a postdoc researcher. Furthermore, sie is part of the Product Owner Board of the TU Graz Catrobat project. Her research focuses on the aspect of human-computer interaction, especially with regard to usability, security, and protection of private data for adults and teenagers. During her dissertation, she focused on agile authentication systems. She researched and developed such systems specifically with regard to user-friendliness. In the Catrobat project, she has her research focus on the usability of visual programming languages. On the one hand, she tries to introduce women to programming through the students who do their numerous student research projects with her and on the other hand through projects like Code'n'Stitch which are conducted in the schools. Email: – Address: Inffeldg. 16b, 8010 Graz, Austria.

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The Catrobat Embroidery Designer has a lot of possibilities for young developers and creative minds. With this stitching app, you can create your own designs and patterns, which can be stitched with an embroidery machine. We will present opportunities and ways to teach students or interested users with some mathematical skills. First of all, we show how to use the Catrobat Embroidery Designer (or as equal the Pocket Code app with stitching extension). Further on we will present successfully proven teaching material, which can be easily used by teachers or students. The beauty of teaching these mathematical skills with Catrobat Embroidery Designer lies in its wide-scale starting at simple examples to a creative and infinite range of applications. For instance, if you want to create a regular pattern (which could look like a flower), you can program some circles where each needs to be turned by its beginning angle. To obtain a regular pattern one must calculate a beginning turn angle by dividing the “magical” 360 degrees by the number of circles used. ( This simple example shows how easy it can be to teach not only mathematical skills but also mathematical understanding for the students.

Pocket Code is an education app, which is developed by the free and open-source project Catrobat with its roots at Graz University of Technology in Austria ( for Android and for iOS). Pocket Code allows users to create programs in a playful way on mobile phones. Similar to existing desktop-based frameworks, such as Scratch or Snap!, the app uses visual blocks of code to make easy programming experience possible for people with no programming knowledge or low programming skills. In the scope of the Catrobat Embroidery Designer, the app can program embroidery machines similar to the Austrian TurtleStitch project ( on a desktop-based environment. As a result, self-programmed designs and patterns can be stitched on clothes or bags, so the young people have something they can be proud of, something they can wear and show to others.

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30 min
Zoom 2
Snap!Con 2020
Short Talk
Short Talk