The LNCS journal Transactions on Computational Science reflects recent developments in the field of Computational Science, conceiving the field not as a mere ancillary science but rather as an innovative approach supporting many other scientific disciplines. The journal focuses on original high-quality research in the realm of computational science in parallel and distributed environments, encompassing the facilitating theoretical foundations and the applications of large-scale computations and massive data processing. It addresses researchers and practitioners in areas ranging from aerospace to biochemistry, from electronics to geosciences, from mathematics to software architecture, presenting verifiable computational methods, findings, and solutions, and enabling industrial users to apply techniques of leading-edge, large-scale, high performance computational methods. This, the 33rd issue of the Transactions on Computational Science, focusses on computational geometry and computability, with applications in IoT (Internet of Things), Bioinformatics, and WBAN (Wireless Body Area Networks). Three of the seven papers constitute extended versions of papers presented at the 18th International Workshop on Computational Geometry and Security Applications, CGSA 2017, held in Trieste, Italy, in June 2017.