android - Google play says: "You need to use a different package name" - why?

Question

I have already published an app called com.mycompany.mygame on google play.

I then decided to publish an ad free version of it. I did not change the package name in eclipse because I noticed that in the "export" process you have the opportunity to have the final apk set as anything you like. So I set it there as com.mycompany.mygameaf - note the additional "af" on the end. But then when tried to upload it to the market, google said:

You need to use a different package name because "com.mycompany.mygame" is already used by one of your other applications

So now I'm confused. Is the complaint because I'm not allowed to have an apk that is a name which is and extension of a previous app? Or does the final apk somehow have knowledge of what the original name was?

What is the easiest way to resolve this?

Answer 1

Apart from correcting app name in the Manifest I also had to change applicationId in the app's gradle.build file.

 defaultConfig {
    applicationId "com.example.changednameofmyapp"
    ...
}

Also, if you're using ProGuard, do not forget to change appropriate rules in your proguard-rules.pro

Just search the old package name in the whole project and change it.