Use for questions about using Google API in web applications as end-user, i.e. creating an spreadsheet custom function .
IMPORTANT: If you are will ask a question about developing web application please checkout Where can I ask a question about developing web applications?
Question about Google APIs per-se are off-topic here but we allow questions about how to use an API on web application that include an extension mechanism for end users like macros, scripts, user defined functions.
From https://en.wikipedia.org/wiki/Google_APIs
Google APIs is a set of application programming interfaces (APIs) developed by Google which allow communication with Google Services and their integration to other services. Examples of these include Search, Gmail, Translate or Google Maps. Third-party apps can use these APIs to take advantage of or extend the functionality of the existing services.
