Abstract: A wearable computing unit with module connection sites can incorporate many different extension types, such as sensors, indicators or executable code, providing many different functionalities. This allows for combining hardware and computing configurations from different origins. Assembly with instant module connection feedback and integration assistance allows users to customize function with ease. For example, configurations can be selected from a database or shared with other users. Mechanical connectors provide multiple modes of wearing the modular device, including the combination with jewelry. This extends its application to user groups with specific aesthetic expectations.