The SugarSync Go SDK by Jeff Buchbinder interacts with the API to implement syncing features into applications. Resources include code to get authentication token, get new file location, get user info, upload file, and create new folder.
Roll-your-own API service Usergrid has been acquired by API management company Apigee. Usergrid could potentially help Apigee reach out to mobile developers increasingly finding themselves needing APIs to interact with their apps. It's part of a trend of developers not only being API consumers, but also API providers--at least privately to their own apps.
Zootle, UK based hosted CRM provider, offers most of its features through the SalesSystemCRM API. From prospecting to order processing, the API allows developers to integrate an entire ecommerce solution with its existing website and apps. The SalesSystemCRM app suite already focused and tailored to budgets in the SME space. However, an API makes the CRM provider even more attractive to businesses strapped for IT resources.