Changing a currently running apps settings?


I’m currently using appium to test an iOS application, The application has a plist file used for settings, which I have been editing in a sort of hacky method.

So normally, the file is located in a directory like the following,

I am able to get the simulator ID, but how do I get the application ID for the currently running application?

I know not exactly an appium only question, but I’m struggling.