I’m into Kotlin, because it’s a new (quite new) programming language, that solves all the Java problems, especially on Android. You can simply use Lambda expressions and much more on any API version. I also used Kotlin in production in my open sourced newsreader app NewsCatchr. Here I’ll share some of the sources, that helped me getting some knowledge in Kotlin:
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Libraries are a bunch of code that simplifies developing of certain features and prevent you from reinventing the wheel. Because most Android libraries are open source it’s also possible to fork and modify them. But you should take care about the specific licenses.
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