progress:

Android

• it is possible to create more AVDs with different Android versions and to run them in parallel

Parallel test execution

• Appium natively supports parallel test execution [1] or Selenium grid can be used [2]
• there is an issue in Appium which prevents parallel execution of tests for Android apps with multiple browser windows [3] - so it is not possible to test Auth for Android Cordova in parallel

[1] http://appium.io/docs/en/advanced-concepts/parallel-tests/
[2] http://appium.io/docs/en/advanced-concepts/grid/
[3] https://github.com/appium/appium/issues/9555