Voting Advice Applications (VAAs) are online tools that assist citizens with their voting decisions. They are offered to voters before elections in many countries and have experienced remarkable success. Recently flourishing research on VAAs addresses this phenomenon and provides explanations for the dissemination and popularity of these tools. Moreover, VAAs have been analyzed regarding their effects on political parties, candidates, and on voters in regard to their electoral behavior. Research shows that using a VAA indeed makes a difference, while the effect depends strongly on the way a VAA is designed and by whom it is used. The abundance of data generated by VAAs bears potential for comparative studies of public opinion and party systems over time and across countries, and thereby bridges research on VAAs to general questions of political science research.