title: What's the difference between src/androidtest and src/test folders?
body: <p>In a project, in Android Studio, by default, there are two test folders.</p>
  
  <p>The first is <code>src/androidTest</code>. This folder already existed in the previous version of Android Studio. Nevertheless, there is now a new test folder, by default, <code>src/test</code>, and new dependence, <code>testCompile 'junit: junit: 4.12'</code> in <code>build.gradle</code>.</p>
  
  <p>Which folder do I use for testing? What are the differences between the two?</p>