At one point, there was a dedicated mobile SDET (Software Developer Engineer in Test) team that handled writing all device tests by following the usual flow of working with developers and product managers to understand the features they were testing to create test plans for all their automation tests. At Netflix, SDETs were developers with a focus on testing; they wrote Automation tests with Espresso or UIAutomator; they also built frameworks for testing and integrated 3rd party testing frameworks. Press enter or click to view image in full size Test Pyramid showing layers from bottom to top of: unit tests, screenshot tests, E2E automation tests, smoke tests