Payleven, the Square equivalent for the world outside of the US, has launched an API to complement its mobile payment device. Prior to the API, use of Payleven's mobile payment device required downloading the Payleven app (similar to Square's current model). However, the API allows developers to integrate Payleven's functionality within third party apps.
Among the 25 finance-related APIs now listed on ProgrammableWeb, there are services from old and new and large and small companies. Overall, most current business and finance APIs fall into one of two categories: APIs from SaaS-based management services, and APIs that provide financial markets data.