Tomislav Kotnik is the founder and editor-in-chief of the technology media company VIDI, which has been publishing the popular IT magazine VIDI and many popular technology web portals for 30 years. He is the publisher of more than 50 professional IT books. On behalf of the VIDI company and the Ruđer Bošković Institute, he founded the first Croatian award exclusively for high-tech innovations, the VIDI e-novation Award, which in its 15 years of existence has rewarded over 70 innovative projects, some of which, like Mate Rimac, have become globally recognized innovations. In 2002 he initiated the establishment of the Prime Minister’s Web Award for the best web projects. In July 2003 he initiated and organised the first virtual session of the Government of the Republic of Croatia held via the Internet, which was held in this form for the first time in the world.

2017. He participates in the team on the creation of the Strategic Framework for the Digital Maturation of Schools and the School System in the Republic of Croatia (2030). At the end of 2019 in cooperation with several technological companies and associations, he led the development project of the first Croatian development multifunctional microcomputer VIDI X, which is available today for over 40,000 students in more than 160 schools and colleges throughout Croatia, and serves for practical STEM education and the development of small and innovative projects in in the field of IoT and simpler robotic systems. VIDI X as a platform for STEM education is actively used today even by schools in the USA.

In the summer of 2023, he was invited by the well-known American publisher of technological literature, Manning Publications Co. to be one of the reviewers of the book AI: Reality and Illusion, by the American author Dr. Akli Adjaouta, a famous scientist, professor and entrepreneur and holder of 28 technological patents.