We are developing one prestigious product. Can anyone tell me which one is best to use for the backend? firebase or MySQL database/Some OtherDb? This app has features like. Users, profiles management, payments and tracking, and several other things
Seems to me that you can use both equally well.
Note that Firebase is a Google service based on a key-value store, whereas mySQL is a relational database based on tables.
For Firebase only the basic tier is free, whereas mysql is completely free (unless you decide to pay someone, for professional support, perhaps)
Good luck with your prestigious product.