Big techs have gained a predominant footing in the digital market thanks to their ability to retain users and reduce any space for other operators to achieve independence in the market. These US and Chinese companies have acquired and consolidated their market power thanks to their ecosystem structure and the offer of multiple services, mainly payment services. In order to gain a complete understanding of the development and consolidation of these ecosystems, it is crucial to analyse the methods, conditions, and timing of this offer of payment services. However, the offer of these services entails new risks for financial stability which can increase if the platforms decide to issue stablecoins. Indeed any issuance of stablecoins differentiated by ecosystem and specialized by function could generate a potential unbundling of the monetary function.