3km is a mobile application that uses GPS technology to provide a convenient, reliable, and safe platform for buying and selling second-hand items. Developed by 3km Technology, this application aims to be a breakthrough in the field of online classifieds, solving the inherent problems of traditional platforms. With 3km, users can easily find products within a 3km radius, post items for sale, and chat with buyers to lock in prices. The application also offers live chat with the seller/buyer before deciding to meet or transact, ensuring safer transactions. In addition to buying and selling products, users can also find services such as home repairs, pet care, and job listings. The app is free to download and available on both App Store and Google Play Market.