This topic describes how to integrate the Google Play Billing Library into| Android Developers
Learn about using in-app purchase and StoreKit framework to sell items within your apps, like premium content, virtual goods, and subscriptions.| Apple Developer
Your partner for growing a business on Google Play. Find the tools and guidance you need to release, monetize and grow your apps and games.| play.google.com
Agreements and Guidelines for Apple Developers| developer.apple.com
Google Play's billing system is a service that enables you to sell digital products| Android Developers
In this guide, we will explore the art of mobile app retention—from benefits and challenges to the most effective retention strategies.| Business of Apps
Xcode includes everything you need to develop, test, and distribute apps across all Apple platforms.| Apple Developer