This app was mentioned in 5 comments, with an average of 2.40 upvotes
Mechanic Escape (a runner) and Puddle+ (a logics game in which you guide a puddle of fuid) went from $2,99 to $0,99
https://play.google.com/store/apps/details?id=com.playdigious.mechanicescape&hl=en https://play.google.com/store/apps/details?id=com.eneko.puddle&hl=en
Could be either <em>Mechanic Escape</em> or <em>Volt</em> (aka 1 Volt).