What database is used for Android mobile app development?

For Android mobile app development, the most commonly used databases are SQLite, Room (an abstraction layer over SQLite), and Realm.

1. SQLite:

   • A lightweight, file-based relational database that doesn’t require a separate server process. It’s embedded in Android by default, making it a go-to choice for simple to moderate data storage needs.
   • Example: Storing user preferences, cached data, or small datasets locally.
   • When to use: When you need a simple, fast, and reliable relational database without complex setup.

2. Room (by Android Jetpack):

   • An ORM (Object-Relational Mapping) library that provides an abstraction over SQLite, making database interactions more intuitive and reducing boilerplate code. It includes compile-time checks for SQL queries.
   • Example: Managing structured data like user profiles, transactions, or app content with relationships between tables.
   • When to use: For modern Android apps where you want type safety, better readability, and easier maintenance compared to raw SQLite.

3. Realm:

   • A NoSQL, object-oriented database designed for mobile apps. It offers faster performance than SQLite for certain use cases and supports real-time data synchronization.
   • Example: Storing complex objects, offline-first apps, or apps requiring real-time updates (e.g., chat apps).
   • When to use: When you need high performance, offline support, or a simpler non-relational data model.

For cloud-based database needs (e.g., syncing data across devices), you can integrate Tencent Cloud’s Database services like TencentDB for MySQL/PostgreSQL (for structured data) or Tencent Cloud NoSQL (MongoDB-compatible) for flexible schemas. These services ensure scalability, reliability, and seamless integration with Android apps via APIs.

Example of Room in Android (Kotlin):

@Entity(tableName = "users")  
data class User(  
    @PrimaryKey val id: Int,  
    val name: String,  
    val email: String  
)  

@Dao  
interface UserDao {  
    @Insert  
    fun insert(user: User)  

    @Query("SELECT * FROM users")  
    fun getAllUsers(): List<User>  
}  

@Database(entities = [User::class], version = 1)  
abstract class AppDatabase : RoomDatabase() {  
    abstract fun userDao(): UserDao  
}  

Choose the database based on your app’s complexity, data structure, and performance requirements.