The KiSSmetrics Ruby SDK by Kissmetrics allows API communication to implement marketing optimization features into applications. It aims to engage users and analyze behaviors for customization purposes. In the usage section, developers can access methods with an Api Key.
Last month, GraphEffect announced an API that allows multiple parties/companies to collaborate on projects using their own marketing/collaboration tools. Now, GraphEffect has launched another platform, Shift.com, that empowers applications to communicate with each other.
With huge budgets spent on marketing, it's probably a good idea to keep track of which marketing avenues are working and which aren't. Call Tracking Metrics is a simple telephone call tracking service that aims at helping users link incoming calls to specific marketing campaigns and in so doing, easily track and analyze the amount of calls received due to that particular campaign. The Call Tracking Metrics API provides access to this functionality.