This book summarizes the research findings presented at the 3rd International Conference on Novel & Intelligent Digital Systems (NiDS 2023). NiDS 2023 held in Athens, Greece, during September 28-29, 2023, under the auspices of the Institute of Intelligent Systems. The conference was implemented hybrid, allowing participants to attend it either online or onsite. NiDS 2023 places significant importance on the innovations within intelligent systems and the collaborative research that empowers and enriches artificial intelligence (AI) in software development. It encourages high-quality research, establishing a forum for investigating the obstacles and cutting-edge breakthroughs in AI. The conference is designed for experts, researchers, and scholars in artificial and computational intelligence, as well as computer science in general, offering them the opportunity to delve into relevant, interconnected, and mutually complementary fields. By facilitating the exchange of ideas, the conference strengthens and broadens the network of researchers, academics, and industry representatives.