Android Testing: UIAutomator vs Espresso

Question

I was seeking for test frameworks for Android UI automation and I stumbled upon UI Automator and Espresso and this is the part I am confused about

Answer 1

When using UIAutomator you must use an 18+ API while with Espresso, you can go as low as API 8.

As the Android documentation states, multi-application tests should be done with UIAutomator while if you only want the tests to run inside of your own app package you can use Espresso.

At the bottom of this documentation's page, you can find the introduction, as well as examples to both of these testing styles.