How to implement the exchange and addition of data already in custom android applications?

Question

Android

I am writing the first more or less worthy Android application and I don’t know how best to implement the exchange and addition of data to already user applications? To be honest, I can’t even imagine how this is done through the server or through some other magical actions, if you advise any books or sites on the topic, I will be immensely grateful, but it would be better to read everything already here from the words of those who already know the developers) Thank you in advance)

Answer 1

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