Client-server application for Android?

Question

Database

In general, you need to write the most simple server with a database for an Android application.
What DBMS and language to use?
Where can I read in detail.

Tried on spring but did not understand anything)

Answer 1

Back is the one you know best.
For me, spring, especially spring booth, is quite simple. Unless, of course, you start to get into some kind of wilds. What difference does it make which front?

Answer 2

The easiest, as for me, is PHP + Mariadb (analogous to mysql).
Read about the Rest API for Android.