• by Steve Smith  @popeyesm, August 27, 2013

While some aspects of the Apple App Store have always been as inscrutable as the tech brand itself, the all-important rankings within this virtual shop seem to have been determined by a combination of total app downloads and trending. But app marketing firm Fiksu says that it detects some changes to the ranking algorithms in recent weeks. According to the company at its blog, Apple now seems to be testing a ranking system that adds user ratings of an app into the mix.

“In late July, we first began to notice apps unexpectedly shifting position without a corresponding increase or decrease in downloads,” writes Tom Cummings. “Upon closer inspection, we discovered these position changes correlated with the apps’ ratings.”

According to the company’s preliminary analysis, apps that received a user’s score of four stars or above seem to get an otherwise unexplained boost in their rank in the App Store Top Charts sections. Meanwhile, apps with user ratings of less than three stars seemed to lose some of their rank in the charts.

At the same time, Fiksu detected a change in the ranking update schedule in the App Store. Previously, rankings appeared to be refreshed every 15 minutes. But now the updates occur every three hours. Fiksu speculates that Apple may be lengthening the update time in order to adjust for app marketers that try to game the system via robot downloads that can spike app popularity unnaturally.

Fiksu suggests that these changes may only be in a testing phase, and may indicate even larger changes to the App Store to come. There have been rumors that Apple may begin considering app uninstall rates as well as social reach in determining rank. With the looming launch of new iPhones in September as well as the iOS 7 update to all its devices, Apple must be preparing for the inevitable increase in App Store use as well as the inevitable jockeying for leaderboard position by app developers.

The company recommends that developers continue to regard volume and velocity as key elements to achieving rank. But they also recommend that developers be especially vigilant in monitoring user feedback and responding to criticism and concerns with updates.