How do I know my Android API version?

Tap the “Software Information” option on the About Phone menu. The first entry on the page that loads will be your current Android software version.

What is an API in Android?

API = Application Programming Interface

An API is a set of programming instructions and standards for accessing a web tool or database. A software company releases its API to the public so other software developers can design products that are powered by its service. The API is usually packaged in an SDK.