This book features a collection of high-quality, peer-reviewed papers presented at International Conference on Ubiquitous Intelligent Systems (ICUIS 2021) organized by Shree Venkateshwara Hi-Tech Engineering College, Tamil Nadu, India, during April 16-17, 2021. The book covers topics such as cloud computing, mobile computing and networks, embedded computing frameworks, modeling and analysis of ubiquitous information systems, communication networking models, big data models and applications, ubiquitous information processing systems, next-generation ubiquitous networks and protocols, advanced intelligent systems, Internet of things, wireless communication and storage networks, intelligent information retrieval techniques, AI-based intelligent information visualization techniques, cognitive informatics, smart automation systems, healthcare informatics and bioinformatics models, security and privacy of intelligent information systems, and smart distributed information systems.