COSS is a young cryptocurrency exchange that was registered in 2017. It is not included in the TOP-100 of the Coinmarketcap rating, its turnover is at an average level. KOSS provides an over-the-counter trading platform and news service. It also has its own COS token. There are a lot of reviews on the web about coss.io, and they are seriously different. Therefore, we decided to make a detailed review of the cryptocurrency exchange, consider its functionality and understand the opinions of users about the company. Overview of the site “KOSS” There is no Russian-language version on the site, so the company is not very popular in the CIS countries. On the main page, COSS advertises its own token and commission in favor of traders. There are six items in the top menu: “Cryptocurrency Exchange”; public api; “Commissions”; “Entrance”; “Registration”; “Language Selection”.