App discovery firm Appsfire said it is introducing “a powerful and innovative signal to assess whether an app is worth downloading.”

Called App Score, it is said to process “dozens” of parameters several times per day across the iOS App Store to generate a single value.

It notes that this goes beyond the current ratings, rankings and review for an app to analyse its performance over time, incorporating additional metadata and reviews from across the web, identifying suspicious behaviour, and synthesising a publisher’s record across its portfolio of apps.

In a blog post, the company identified a number of shortcomings with the current system. For example, rankings only identify the top 200 apps; charts can be “gamed” by marketers, meaning that results can be little more than “a measure of marketing dollars;” rankings are only an indication of performance at one time, rather than a measure of sustained success; and ratings are irrelevant for new apps, and can also be gamed.

“Ratings and reviews are relevant, but to derive value from them you need to see the forest through the trees – weeding out apps which have gamed the system while rewarding apps which have generated genuine, positive ratings and reviews around the world and around the web,” Appsfire said.

In addition to taking information from the App Store, App Score assesses mentions on Twitter and Facebook, mentions on key review sites, and “more” to inform its results.

The company noted that the service may be less accurate where little information is available and, because it is based on algorithmic assessment, “a few apps could be trapped by mistake.” It said that this will soon be completed by a crowdsourced system in addition to safeguards intended to address weaknesses.