How do I return to the normal game when I want to stop playing Multiplayer Boom Town?

The screenshots below show how to stop playing Multiplayer Boom Town and return to the main game:

Some people say that the green button doesn't appear for them. If that's your situation, you can exit the app by following the directions on this page: https://spryfox.zendesk.com/entries/21739207-How-do-I-fully-exit-an-app- . Please also email support@spryfox.com with your device specifications so that this problem can be corrected in the future.