What factors affect Apple's Algorithm?

After listening to many of our developers we have compiled a list of potential factors that affect search visibility.

Factors with Keywords that may affect search ranking:
User Review Keywords
3rd Party Review Site Keywords
Names of in-app Purchase Items

Quantitative signals that may affect ranking:
# of Reviews
# of Ratings
Momentum of new reviews & ratings
# Cumulative ratings
# FB Likes
# Downloads
Engagement/time spent
Download Momentum
Revenue Momentum

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