How to verify the application with the imei of a smartphone?

Question

Android

Hello guys, please tell me what code should be implemented in the application. In general, the essence is this, I have an application, I don’t want to sell it on Google Play, because there it is constantly blocked either for advertising or for something else, they bothered me, my application is not massive, it is designed for a very narrow circle of users , in general, I want to sell it myself for a small amount, the bottom line is that I don’t want me to sell it to one, but he sent it out for free to anyone he wants, I want to make it so that, for example, by the last imei digits, that is, not the whole number , but only its last 4 digits, the application seemed to be attached to it, that is, so that, for example, if the user wants to transfer the application, it would not work without finding matches with those 4 digits and give a message something like "you must buy the application ..." I immediately say

Answer 1

stackoverflow.com/questions/1972381/how-to-program...
you are like the first day on the Internet.
You must do it not by imei - maybe a stupid user will not be able to rebuild, but he can turn to someone who can. and further to distribute / resell
it is necessary to make an application with verification via the Internet. although here you can cut out a piece of unnecessary code

Answer 2

> that is, the user sends me the last 4 digits of his imei, I hammer them into the application, make an assembly, send it to the user, he installs it, and the application compares the 4 digits sewn into it with the last 4 imei digits,
It seems that you answered your own question.

Answer 3

And what prevents you from recompiling the application and making it work on all phones?