What methods can be used to exchange data between two applications?

In Android, there are several methods to exchange data between two applications:

1. Intent — the most common way. Data can be sent via explicit or implicit intents using putExtra.

2. Content Provider — provides structured access to data, allowing one application to read and modify data of another.

3. Shared Preferences with the MODE_WORLD_READABLE flag (deprecated and unsafe method, not recommended).

4. Files in external storage — applications can read and write files if they have the appropriate permissions.

5. AIDL (Android Interface Definition Language) — for inter-process communication (IPC), when methods of another application need to be called.

6. Broadcast Receiver — sending and receiving broadcast messages with data.

Example of data transfer via Intent:

val intent = Intent().apply {
    action = "com.example.ACTION_SEND_DATA"
    putExtra("key", "value")
}
startActivity(intent)