How to get Django and database working properly?

Question

Django

Developing an iOS/Android app using Django + REST API framework (to interact with mobile apps).
Back-end architecture question:
1. There is a back-end part developed on Django;
2. Inside the Django project there are several apps (app1, app2, app3) for a more convenient architecture. Each app is responsible for its own set of functionality when interacting with the front-end;
3. There is a DB for the project. The DB has 40 tables. Some tables have over 10,000 entries, one has over 100,000;
Question:
Does it make sense for each app to make its own DB, spread the tables over the 3rd DB and establish interaction between the DB of each app? If not, then won't this cause an excessive load on the back-end part when a large number of users access the DB at the same time with different queries?

Answer 1

Splitting makes sense only if the resulting DBs are not interconnected.
About the load, load testing is done, the bottleneck is determined, optimized. Repeat until you get the result that suits you.