The 'satan' frequency in the reviews vs. the rest of the app store is a smoking gun. https://sensortower.com/flappy-bird-scripted-reviews-analysi...
" I'm not sure if that is due to genuine virality & copy cat ommentors, an army of keyword-fed reviewers, or an advanced spintax generator. "
"I still have no idea whether or not Flappy Bird gamed the system"
Not much of a smoking gun there.