Streaming Assets

Unity combines ScenesA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
See in Glossary and Assets into binary files inside the generated Player when it builds the Project. However, you can place files into the normal filesystem on the target machine to make them available using a pathname. For example, for deploying a movie file on iOS devices, the original movie file must be available from a location in the filesystem to play using the PlayMovie function. This folder can also include AssetBundles that you intend to distribute directly in the Player installation, rather than downloading them on-demand.

Unity copies any files placed in the folder called StreamingAssets (case-sensitive) in a Unity Project verbatim to a particular folder on the target machine. To retrieve the folder, use the Application.streamingAssetsPath property. It’s always best to use Application.streamingAssetsPath to get the location of the StreamingAssets folder, because it always points to the correct location on the platform where the application is running.

The location returned by Application.streamingAssetsPath varies per platform:

• Most platforms (Unity Editor, Windows, Linux players) use Application.dataPath + "/StreamingAssets".
• macOS player uses Application.dataPath + "/Resources/Data/StreamingAssets".
• iOS uses Application.dataPath + "/Raw".
• Android uses files inside a compressed APKThe Android Package format output by Unity. An APK is automatically deployed to your device when you select File > Build & Run. More info
  See in Glossary/JAR file, "jar:file://" + Application.dataPath + "!/assets".
• On Web, Application.streamingAssetsPath returns a HTTP URL that points to the StreamingAssets/ path on the web server. For example, http://localhost:8000/unity_webgl_build/StreamingAssets/ is returned when your application is running against a local development server.

Accessing streaming assets

On Android and the Web platform, it’s not possible to access the streaming asset files directly via file system APIs and streamingAssets path because these platforms return a URL. Use the UnityWebRequest class to access the content instead.

In general, when using the UnityWebRequest class to access the streaming asset files on all the platforms, create a new instance of System.Uri(filePath) and pass it to UnityWebRequest.uri.

Notes:

• The streamingAssets path is read-only. Don’t modify or write new files to the streamingAssets directory at runtime.
• .dll and script files located in the StreamingAssets folder aren’t included during script compilation.
• Asset Bundles and Addressables are alternative ways of accessing content that’s not part of regular game build data, and preferred over Streaming Assets folder.