Feature requests are enhancements for existing features or requests for new features proposed by end users on the open forums, which can reflect the users' wishes and represent the users' needs. Feature requests play a vital role in improving user satisfaction and improving product competitiveness. It has become an important source of software requirements. However, feature requests are different from traditional requirements in terms of source, content and forms. Thus, there must be differences in applying feature requests to software development than traditional requirements. At present, there are many researches about feature requests on different topics, e.g., classification, prioritization, quality management, and so on. With the continuous increase of related researches, the necessity of a survey of user feature requests analysis and processing has increased. In this paper, we investigated 121 academic research papers on how to analyze and process feature requests in the software development process. We sort the existing researches from the perspective of applying feature requests to the software development process. We summarized the research topics on feature requests and investigated the research progress. Besides, we mapped the feature requests research topics to traditional requirements engineering processes. We analyze the existing research methods and point out research gaps. Finally, in order to provide guidance for future researches, a perspective of the future work in this research area is discussed.