Purpose - This study aims to introduce and characterize a specific form of self-service technology (SST), customer self-service devices (SSDs), as well as propose and apply a classification scheme of SSDs to encourage future research on such SSTs. Design/methodology/approach - The paper is based on conceptual development of customer SSDs and exploratory qualitative insight from representatives of companies offering various types of SSDs. Findings - This paper introduces SSDs as customer-possessed and controlled smart service devices aiming to solve problems from the customer's perspective, often within completely new, customer-defined service processes and ecosystems. SSDs are not confined to the company-controlled service environment, and customers may thus use them wherever and whenever they so wish. The study characterizes SSDs based on service and customer use features, as well as on the subject of the service act (self/other vs belongings) and nature of service act (monitoring vs acting). Research limitations/implications - This study is limited to conceptual exploration with qualitative insights from six companies. Future research is needed to empirically study different SSDs by using both qualitative and quantitative approaches in various settings. Originality/value - The paper conceptualizes SSDs as an extension to the traditional SST framework. It contributes to the understanding of how personal handheld devices can contribute to customer experiences. It provides research directions to stimulate further research in SSTs.