User feedback is indispensable in software evolution. Previous work has proposed ways for automatically extracting requirements, bug reports and other valuable information from feedback. However, little is actually known about how user feedback— especially the one available through newer channels, such as social media—is incorporated in development processes. To date, only a few case studies discuss the matter and the results are not always consistent. We carried out a mixed methods study to understand the current state of practice of harnessing user feedback in software development. Qualitatively, we performed interviews with 18 software practitioners to get a deeper understanding of the role of user feedback in software evolution. Quantitatively, we surveyed 101 software practitioners to cross-validate the interview findings and improve the generalizability of the results. We found that feedback is captured to (1) identify bugs, features and usability issues, (2) get a better understanding of the user, and (3) prioritize requirements. Our results indicate that analyzing feedback is time-consuming and has a number of challenges. Among them, feedback is typically analyzed manually and is spread over a wide range of channels and company departments. Our findings stress the importance for cross-department cooperation and call for the exploration of tools that can centralize user feedback.