Senior Software Engineer @IdeasOnCanvas GmbH. Matthias Tretter is the lead developer at IdeasOnCanvas, where he works on MindNode for iOS, macOS and watchOS (http://mindnode.com). Matthias is passionate about a lot of things, but front and foremost technology, psychology and especially the intersection of both. Therefore he is equally interested in technical aspects of a product, as well as its user experience. Recently he developed a big passion for accessibility and what it takes to make apps truly great to use for impaired users.