Espresso
Espresso is a native testing framework for Android to write reliable UI tests. Google released the Espresso framework in October 2013 and, as of release version 2.0, Espresso is part of the Android Support Repository. One of the important features in Espresso is that it automatically synchronizes your test actions with the user interface of your application. The framework also ensures that your activity is started before the test runs. It can also force a test to wait until all observer background activities have finished, which is sometimes a problem with other testing frameworks.
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