Lume is an iOS application focusing on the second-hand trading of cosmetics in Europe and the United States, with the core positioning of "lightweight trading and social connection". It does not involve complex design and purchase, order supply chain and other functions, focusing on providing users with convenient commodity release channels and efficient Instant messaging (IM) transaction communication scenarios, aiming to build a safe, simple and focused cosmetics second-hand circulation platform to meet the needs of European and American users for idle cosmetics processing and cost-effective beauty products.