Atari had a kind of "app store", from 1982 to 1984, for Atari 8-bit computer users, with the Atari Program eXchange, or APX. It was a mail-order catalog any Atari user could get from Atari that allowed them to buy programs written by Atari, or independent authors. I'm not sure what criteria Atari used for what could be included in the catalog. Everything in it was sold through APX.
Mark Miller
in reply to Hank G • • •[https://www.atariarchives.org/APX/about.php](What was Atari Program Exchange?)
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