Cross-platform development is developing an app for multiple platforms such as Android, iOS, Windows, and Mac. This means that the same code base will run on all these platforms with minor differences in design or user experience. Hybrid mobile app development combines both cross-platform and platform-specific development. This way, the developers create an app primarily for one platform (for example, iOS) and then use different code to create a version of the app that runs on other platforms (for example, Android).