Monetizing with ads and in-app purchases
There are different business models for mobile apps. Rather than expecting users to pay for an app before they can use it, it is fairly common to offer apps for free. In this case, you can monetize your apps by displaying ads or by offering in-app purchases.
Delphi comes with a cross-platform TInAppPurchase
component that is available on the Services tab in the Tool Palette. With this component, you can sell virtual content within your app in a single way by using the Google Play in-app billing service on Android and the Apple iOS in-app purchase service on iOS. The details of using in-app purchases are different on both platforms and are very well documented on Embarcadero DocWiki.
Another possible business model is to embed advertisements in your apps. FireMonkey comes with a TBannerAd
component that you can use to easily display ads in your app. This is a visual component, as you need to indicate which portion of the UI of your application...