Dagger2 is written in Java and Koin in Kotlin, and using both libraries in a Kotlin project should not be a challenge. However, implementing Koin in Java could be a little tricky. One notable piece of information worth mentioning is that while Dagger2 is a fully acknowledged DI project, whereas Koin is only described as a Service Locator. In Android programming, handling dependency is a big concern. For the past few years, we have been using Dagger2 for the dependency injection.
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