What/Where is the SharePoint App server, where to point the DNS

I am trying to setup the SharePoint 2013 farm for apps.

We have 2 farms:

Test DB Server Test Central Admin Test Front End 1 Test Front End 2

Prod DB Server Prod Central Admin Prod Front End 1 Prod Front End 2

and a Content Server that will eventually publish to prod and or test.

I am working on the Content Server. I created the web applications, site collection and solution installed and ready. The App Management Service and Subscription service is running.

Now I need to install my app part so I need to setup my farm for apps...

So out of all these machines what should the app domain be?

I have created an app domin, for example, appsmycorp.com. Where machine on the farm should this "point" to?