Apollo was one of three nearly identical games produced by Williams in 1967 to capitalize off the prominence of the NASA lunar program, along with Blast off and Lunar Shot. Taken as a group they were among the most popular and best-selling games of the decade.
Apollo was the replay version; Blast Off was the add-a-ball version. Lunar Shot was a version of the add-a-ball with modifications to the backglass to conform to Italy's strict anti-gambling laws.
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