We investigate the impact of additional product information generated by the use of mobile apps on purchase decisions. We propose that additional product information provided by mobile apps influences the objective and subjective quality of consumers’ purchase decision positively and reduces consumer confusion while it negatively influences decision efficiency. The results of four experimental studies show that the use of mobile apps positively influences the subjective quality of the decision only under specific conditions, but negatively impacts decision efficiency and also increases consumer confusion. These effects are not only triggered by the use of mobile apps in general, but also depend on several environmental conditions and on the amount of additional product information provided by mobile apps.