The Google Analytics SDK for Android is available to download. The site contains implementation guides to get started, initialize trackers, create XML file, and send an event. Additional resources in the web tabs relate to parameters, example apps such as 'Hello World' & 'Cute Pets' and forum support.
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.