Update (2/27/20 @ 2:40 PM ET): Google will deprecate the Play Console's "Rewarded Product" monetization feature on April 21st.
The games category in the Google Play Store is by far the most popular app section on Android. This isn't to say that there aren't many decent regular apps to use; we highlight multiple new releases from our community members each week. However, mobile games just get more attention from developers because of how much money a good mobile game can make when it's properly monetized. Some developers choose to sell their game at an up-front price while other developers have opted for the free-to-play model. No matter which method a developer goes with, Google has now introduced a way for them to make money while also rewarding the user.
If you've played any F2P mobile games in the last few years then you have likely been inundated by a massive amount of microtransactions. These games usually have two forms of in-game currency—one that you earn while playing the game and one that you earn slowly in-game, bought with real money, or both. However, there's been a new trend that gives the user an in-game bonus while also letting the developer make some money from the most frugal of mobile gamers.
It happens in various ways depending on the game but you'll often be offered the ability to watch a video advertisement to receive some sort of bonus. This bonus can come in the form of double the in-game currency for X number of minutes, an extra chance at a particular level, or anything else that can benefit the user. Developers could add this feature with Unity Ads, but now Google has announced they are building it into the Google Play Billing Library or AIDL interface with only a few additional API calls. The featured is called a "rewarded product" and instructions on how to set it up can be found here.
This means the developer doesn't have to integrate any other SDK into their application or game which should reduce the work required to add this extra monetization opportunity. The feature is powered by Google's Admob technology so developers will have access to the large number of advertisers who they are working with.
Source: Android Developers Blog
Update: Deprecating on April 21
Google's "rewarded product" developer ad program is being cancelled before it leaves beta. The program was started a little over a year ago and allowed for things like watching ads to get in-game currency. Google built this feature into the Google Play Billing Library, but it will be deprecated on April 21st, 2020. Ad requests after that date won't be fulfilled and there won't be a way to view or manage rewarded products in the Play Console. Developers can provide a payout method for revenue from rewarded products before the cutoff date to receive their final payout. There will be a one-time exception for the minimum balance for payout.
Source: Google | Via: Android Police