Providing on-line non downloadable software for user interface integration and developing customized cryptocurrency and blockchain trading orders, trading engines, and trading strategies; providing open­source toolkit software for user interface integration and developing customized cryptocurrency and blockchain trading orders, trading engines, and trading strategies; application service provider featuring application programming interface (API) software for user interface integration and developing customized cryptocurrency and blockchain trading orders, trading engines, and trading strategies; platform as a service (PAAS) featuring computer software platforms for user interface integration and developing customized cryptocurrency and blockchain trading orders, trading engines, and trading strategies; platform as a service (PAAS) featuring computer software platforms for allowing online peer-to-peer currency financial services, namely, for trading, lending, financing, and exchange of currency, digital currency, virtual currency, valuable tokens, and digital tokens; software development in the framework of software publishing; data storage, authentication and certification via blockchain; providing on-line non downloadable software for user interface integration and developing customized cryptocurrency and blockchain trading orders, trading engines, and trading strategies; data storage and certification via blockchain; electronic storage of cryptocurrency for others; providing on-line non-­downloadable computer software for use as a cryptocurrency wallet