In consumer and information systems research, it remains unclear how consumers consider smartphone app recommendations in the course of their decision making process that leads to product choices in the physical store. Moreover, it is unclear which type of information smartphone apps should transport to consumers and if there are any customer segmentation criteria for smartphone app design. With respect to the theoretical and managerial importance of recommendation services in the form of smartphone apps we want to shed some light on this topic. Combining literature from the fields of IS and marketing research, we hypothesize that personalized recommendations via smartphone apps can help to boost sales in physical grocery stores. Furthermore, we hypothesize that additional popularity information (in the form of “stars”) does not amplify the positive effect of personalized recommendations. In addition, we assume that the effects of recommendation usage differ for men and women. We conducted a field study with a European grocery retailer to test our hypotheses. Finally, we discuss first implications as well as central limitations of our research and present the next research steps.