User-Generated Content for Location-Based Services: A Review

User-generated content (UGC) has become one of the important ­elements in today’s Internet world. The proliferation of UGC has prompted many efforts to develop useful services using this freely available information. One of the domains of interest is in the field of location-based services (LBS). In this chapter, we present a review of LBS that leverage UGC. We illustrate the differences between conventional LBS and LBS that use UGC in order to highlight the implications of using UGC in LBS. In order to analyze how UGC has been used in LBS, a collection of existing UGC-based LBS have been identified and divided into two groups. It was found that some of the current systems were modeled under the assumption that most of the UGC contributors were honest in providing updates to the systems. However, this does not always correspond to the reality. Hence, the three fundamental requirements for successful UGC-based LBS deployments are discussed in this chapter. These requirements are information trust, user’s privacy protection, and information classification. The state-of-the-art solutions for fulfilling these requirements are listed and discussed. We strongly believe that the quality of UGC used by the system, the protection of contributor’s privacy, and the system’s response time are basic requirements for successful UGC-based LBS.