This study uses exploratory research to develop a taxonomy of smartphone users from the perspective of mobile marketing (MM) and based on nine segmentation criteria identified through a systematic literature review. Based on a two-step cluster analysis, an exploratory factor analysis identifies four segmentation factors with statistical significance: smartphone self-efficacy, mobile-specific innovativeness, mobile users’ information privacy concerns, and personal attachment to the smartphone. These factors are used for cluster analysis of a sample of 1,535 Swiss smartphone users across all ages. Thereby, six different segments of smartphone users were discovered: Always on Techno-Innovators, Abstemious and Anxious Conventionalists, Pragmatic and Competent Cowards, Innocent Late-Night Surfers, Mobile Junkies, Thoughtless Mobile Geeks. The clusters were compared with respect to demographics, used smartphone operating system, ownership of mobile devices, smartphone usage time, number of installed and regularly used apps, frequency of performed smartphone activities, interaction with companies, as well as perception and reception of MM instruments.