Now and then I have seen people try to do absurd things like "try to make the system music app from a Galaxy S4 work on a Nexus 5""try to make the system music app from a Galaxy S4 work on a Nexus 5". Also, there may be other examples. I have seen these things occuring previously, and I also had tried to do things like this at one time before I learnt the hard way that it just wasn't meant to be.
Doing this would involve decompiling APKs, installing libraries and frameworks which would make the matter in discussion so off-topic here that probably the Stack Would Overflow (:)), since we don't encourage development-related questions.
So, the question:
Can we have a canonical question or a help center entry which moderators can direct users to if they have questions like this, and which will explain the problems associated with such ventures and how they are out of scope on Android Enthusiasts?