The best way to reach mobile app and game consumers is by running ads in the form of “meta games,” according to a new study.

The study was conducted by social mobile game developer KamaGames and ad-tech firm Appodeal in an attempt to find out which ad format yields the highest returns in terms of new app installs and cross-selling promotions. The companies said that meta games encourage players to engage in gameplay, using motivators such as daily challenges, personal achievements, or quests. Players also receive notifications of friends’ activity across the portfolio, such as “Joe has begun to play Blackjack.”

Meta games beat out banner ads, rewarded video, and social hooks when it came to driving new app installs.

Like many gaming app developers, KamaGames uses their own games to cross-sell. Cross-selling within one’s own portfolio can be a highly effective way to increase retention, which is extremely important given the saturated gaming app market and the cost of acquisition. Rewarded video has traditionally been recognized as the highest-performing ad format in the area of in-app advertising; in fact, a majority of gaming app developers note video ads deliver the most revenue, as compared to other ad formats. However, when it comes to cross-selling promotions, meta games have the advantages when it comes to actually driving new game installs, the companies said.

To conduct this analysis, KamaGames ran several cross-selling promotions across the KamaGames portfolio including home screen banners and meta games. The performance of the meta games tactics was compared to rewarded videos, which were featured through in-game stores.

Appodeal collected and compared conversion rates across both Android and iOS devices, and found that meta games outperformed the other tactics. Rewarded video actually delivered a higher conversion rate than banner ads, yet the volume of banner ads and their more prominent positioning in games ultimately drove a higher number of installs. Social hooks placed last.

The study concludes that when it comes to cross-selling promotions in gaming, meta games yield the largest return on investment, while also being minimally intrusive to the gameplay. However, the use of rewarded video for cross-selling remains a highly effective tactic that can deliver solid results while also enhancing the gaming experience, and putting unsold advertising inventory to good use.

San Francisco-based Appodeal is an ad-tech firm that increases revenue through an established marketplace where ad networks compete against each other in real-time for every ad impression.