Tapjoy, which rehabilitated itself by shifting its attention onto mobile platforms from Facebook, is looking to keep its edge in the app promotion space as new competitors emerge.

The San Francisco-based company has launched a pay-per-action advertising network that lets developers promote their work to new users and only pay when they make certain actions or reach a higher level in a game.

It’s a more refined approach to how the company’s advertising has worked in the past. Tapjoy built its name and network by letting gamers earn extra virtual currency in mobile apps if they installed apps from other developers. Unlike other mobile advertising, they charge per install, not per impression or click.

Pay-per-action goes a step further, ensuring that when new users download an app, they actually play it. (We’ve seen variants of this model in the past on the Facebook platform through another company, Nanigans.)

With thousands of apps in the company’s network, the accumulated purchasing power of Tapjoy’s users can push a new app into the top echelons of the charts.

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