title: Android Studio: launch an activity of another app when debugging
body: <p>Let's say I have two apps in an Android Studio project: "S_App" is an app that exposes a service, but doesn't have any activities and no GUI. "C_App" is a client app with a GUI that starts the service in S_App.</p>
  
  <p>I want to debug S_App, but I don't know how to do so directly in Android Studio. Since the app itself doesn't do anything and has no GUI, I would need to start C_App to make it do something. However, if I "debug C_App" from Android studio then only C_App is attached to the debugger, but not S_App, which will consequently not hit any breakpoints.</p>
  
  <p>I know you can manually attach a debugger to a process, but that is tedious to do every single time. Isn't there a way I can configure Android Studio so that it attaches the debugger to S_App but actually launches an Activity in C_App? I saw in the "edit configuration" dialogue you can choose a custom activity to launch, but this is strictly limited to activities within the app you're debugging apparently.</p>