In this study, we use a game theoretic model to argue that the presence of online reviews can lead to product quality improvements for independent firms selling experience goods. Exploiting heterogeneous review platform penetration across markets, we test the predictions of our model using a dataset covering 40 thousand U.S. hotels and show that markets with greater TripAdvisor penetration exhibit greater gains in independent hotel quality. Independent hotels located in median penetration TripAdvisor markets improved their quality by .129 stars as measured using composite online travel agent star ratings, erasing 41% of the advantage held by chains in the absence of online reviews. We address measurement noise challenges for quality and platform penetration using state space models to reveal persistent quality and platform penetration trends. Additionally, we resolve endogeneity due to potential unobserved confounds correlated with penetration and quality across markets and time. We do so by exploiting review platforms' imperfect market definitions that divide areas of hotel agglomeration into separate review platform markets, thus pseudo-exogenously assigning hotels in the same area to varying levels of online review exposure. Our research suggest that online reviews play an important role in facilitating competition on quality.