Postgresql – Should I use two Postgres databases for Django on Heroku – dev & prod?

I’m quite new to Django.
I’m building a Django app and want to deploy it to Heroku with Postgres database.
I already installed a Postgres app on Heroku, and have my credentials.

Should I have two databases – one Postgres database with its own settings locally for dev, and one that is on Heroku?

The app is quite simple, so I don’t necessarily need two databases, but maybe it is needed for deployment.