BlastOut is a mobile app that allows people to interact within their own temporary social network. It facilitates local communications: within events and parties, but also at conferences, and enables people to make new connections easily. The application is a mixture of an anonymous imageboard and location-based forum, allowing users to upload a pic into a stream via their mobile app. The stream is geographically limited to a very close proximity of the one who queries. There is a commenting functionality and a way to share real life contacts if wanted by both parties; otherwise, the communication is anonymous. At the core of the solution there was a demand for an extremely effective location matching algorithm. It should have given an immediate answer as to which posts to show to a user given their approximate geographical location. Besides, the customer requested a profound feature-rich filtering.With the help of our team, the product moved from support-heavy and ineffective for this case MySQL database to MongoDB, which is more native for Node.js. The effective implementation of the search and location classification algorithm provided by Blastout in-house engineers enabled the locality-based matching of the app. The product was released to the mobile apps markets.