The most used and popular database packages used in the Flutter are as follows:

sqflite database: It allows to access and manipulate SQLite database.
Firebase database: It will enable you to access and manipulate the cloud database.

In Flutter, one popular database package is “sqflite.” Sqflite is a SQLite database plugin for Flutter, and it provides a simple and efficient way to work with a local database in your Flutter applications. It is widely used for storing and retrieving data in mobile apps built with Flutter.

Flutter, being a versatile framework for building cross-platform mobile applications, supports various database packages. Some popular database packages used in Flutter include:

sqflite: A SQLite plugin for Flutter that provides a simple and easy-to-use interface to interact with SQLite databases.
moor: A persistence library for Flutter and Dart that works with SQLite, supporting reactive queries and easy-to-use APIs.
hive: A lightweight and fast NoSQL database for Flutter and Dart that is easy to use and can be used for storing key-value pairs or more complex data structures.
firebase_database: Firebase Realtime Database is a cloud-hosted NoSQL database provided by Firebase. The firebase_database package allows Flutter apps to interact with the Firebase Realtime Database.
sembast: A NoSQL embedded database for Dart and Flutter applications that provides a key-value store with support for indexes and transactions.

These are just a few examples, and the choice of the database package depends on the specific requirements of your Flutter application.