This project is an iOS application named Aerie, designed for the users who are seeking suitable roommates or room rentals.Aerie is a platform that supports users to post advertisements and real-time chatting, on basis of firebase cloud storage. With this App, users can post roommate wanted advertisements with their requirements for the roommates. Users can sign up using an existing Google account or register accounts using other emails. To personalize their requirements for their roommates, users can alter the input fields to describe their concerns. For example, users can list the expected budget for monthly rental fee, desired location for residence, the sexuality of the roommates, to their postings. Only the posters who send the posting have the privilege to edit or delete their postings. As a result, other users who are looking for roommates can view the postings via Aerie. In terms of negotiations, users can contact the poster of the roommate wanted advertisement using the online chatting feature of Aerie.