Epic Games has released Fortnite on Android, and not through the Google Play Store. Instead, they will self-host the APK on their own website, and also distribute through the Samsung Galaxy Store. There is one reason for this: they want the 30% In-App Purchase cut that Google demands.
As a free-to-play game, Star Trek Timelines needs players to return to the game on a frequent basis over a long period of time.
This is a discussion of the ways developer Disrupter Beam has created effective monetisation and retention strategies for their game.