By matching the political offer with voters ’ preferences, these internet appli-cations assist voters in their decisions. However, despite the growing num-ber of VAA users in several European polities, little is still known about the profile of a typical VAA user, let alone about the impact of VAA usage on individual level attitudes and behavior. Dominant research in this field of-fers contradictory evidence for it suffers from poor data quality, relies on descriptive analysis and fails to tap causality. To remedy these problems this thesis systematically investigates the patterns of VAA usage and its impact on voting preferences, vote choice and electoral turnout. In so doing I em-ploy data from cross sectional election studies, panel surveys and a large N field experiment. First, I demonstrate that VAA usage is more frequent among the young, educated citizens from urban areas. However, addition-ally to these baseline properties, VAA users appear to be considerably more active in political life, they are interested in political issues and they are available to electoral competition. Second, using an experimental researc
