Gambling apps double-crossed the review systems in Google Play and the App Store by posing as a policy-abiding app. Apps made it into the Android official store in August but survived for a longer time in the iOS repository as some of them had been rated more than 100,000 times. Developers created apps with functionality in agreement with the store requirements, such as weather tracking or entertainment, but they come with an API switch feature to control the availability of the illegal content in the app. The accepted content is only a facade maintained until the app becomes available to users.
Source: https://www.bleepingcomputer.com/news/security/fake-apps-sneak-gambling-into-ios-and-android-app-stores/