The KashFlow PHP SDK by Joel Fielder is available to download, found in the tutorial "Integrating with Kashflow using PHP." References explain how to configure the KashFlow account, interact with the API, handle parameters, and create a sales invoice working with the API.
With more than 6,000 active applications making more than 1 billion API calls each month, Intuit has revealed that it is working on a new QuickBooks Online API. The new API, along with the new QuickBooks Online v4, will contain improvements based largely on feedback provided by Intuit's customers.
ZenPayroll, Inc., a cloud-based payroll service provider, has just announced the release of the brand new ZenPayroll API which allows developers to connect HR, Finance, scheduling and other back office applications with the ZenPayroll platform.