After opening an account by a new user (in possession of a "login" and a "password"), it immediately becomes possible to transfer units from one account to another in the base currency called EU-coin. As an option, each user has the possibility of being the “creator of an affinity currency”, that is to say a currency renamed according to the affinities of a group of users. This affinity currency is in turn transferable as soon as it has been validated by a “group of validators”. In addition, the APP also allows you to convert the base currency EU-coin into affinity currency EU-xxx and vice versa. A history of all transfers, in base currency and affinity currencies, is permanently consultable. Each currency created in an affinity manner makes it possible to test a scenario of ecological transition, social transition, or any other type of transition.