AMAZON UNDERGROUND
Amazon Underground: https://www.amazon.com/gp/feature.html?ie=UTF8&docId=1003016361&ref_=&ref_=mas_undrgrnd_flyout&tag=drolif05-20
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In a nutshell, that's the excuse to finish/kill the Daily Free App. Now they don't have to manually select an app, and the system (or developer) will decide when/why one app (or a group of apps) should go in underground vault, to remain free for a period defined by the system/developer.
