The mobile device simulator and emulator nodes work basically the same as the browser nodes on the Selenium Grid. You need to build a bash or PowerShell script to start the Appium server, and in the case of the Android emulator, there is a command-line option to start the emulator. The Appium driver for the iPhone will launch the correct iPhone/iPad simulator and close it when complete.

Let's look at a couple of sample scripts and configuration files to start up the mobile device nodes.