Tree.io provides cloud based Project Management, Sales & CRM and Service Support tools for businesses of all sizes. The API lets users integrate their customer database, CRM, CMS, or e-commerce shopping cart with Tree.io. Users can allow both read and write access to their Tree.io data from almost any application. A range of functionality including creating and returning information about calendars, documents, accounts, projects and more. The API uses RESTful calls and responses are formatted in JSON.