What options other than Firebase are there?

Question

firebase

Asked a question recently.
Is it possible to make your own Instagram with blackjack and other things))
I came across all sorts of articles, but they use Firebase there (it is paid and there is a limit on the number of users).
The question in general is this: how to make everything scalable + possibly cheaper.
To have simply a DB on a server?
Then there is only one server?
Help me figure out how it all works.
In order to make applications for Android / IOS in the future.

Answer 1

good haiku

Answer 2

For a prototype or a small application, firebase is enough. Even the free part of it. If you go to the "Instagram" level, then you will already need your own server there. For example, they speak well of the Amazon ones, but this is not accurate.