Theme Article: Special Section on Security and Sustainability Technologies for Smart Cities Technologies FinderX: A Bluetooth Beacon-Based System for Designing Sustainable Green Smart Cities Raiful Hasan and Ragib Hasan University of Alabama at Birmingham Abstract-Cities offer extensive facilities to enrich the quality of life by utilizing smart devices and sensors. The Internet of Things and smart sensors connect various city services with the inhabitants. The services should be convenient and accessible to all, especially pedestrians and people with visual impairment. However, the lack of information about service locations often limits their availability and use. To this end, we developed FinderX, a Bluetooth beacon-based system to search for the nearest services and amenities. FinderXidentifies the locations of nearby amenities in real time using the signal from attached beacons. The system does not require Internet or other communication infrastructure and can function where the GPS signal is inaccessible. To demonstrate the feasibility of FinderX, we set up a testbed and evaluated the system in an urban environment. We show that FinderXhas adequate usability and feasibility and it reduces the time to find the amenities by 18.98% on average. We also demonstrate that Bluetooth beacons have a lower horizontal error compared to GPS in micropositioning (where semi-indoor or surrounding infrastructure limits signal accessibility), which motivates the use of Bluetooth beacons for such applications. Digital Object Identifier 10.1109/MCE.2021.3076290 Date ofpublication 28 April 2021; date ofcurrent version 6 December 2021. January/February 2022 Published by the IEEE Consumer Technology Society 2162-2248 ß 2021 IEEE 65