# Integrating Unity into native iOS applications > Integrate the Unity Runtime Library into iOS applications. This page describes how to integrate the Unity Runtime Library into iOS native applications with the Unity as a Library feature. You can use this feature to include Unity-powered features, such as 3D/2D Real-Time Rendering, AR Experience, 3D model interaction, or 2D mini-games, in your native application. The Unity Runtime Library exposes controls to manage when and how to load, activate, and unload content in your native application. ## How it works To use Unity as a Library for iOS, first build your Xcode project as usual from Unity. For more information, refer to [Build an iOS application](/engine/6000.3/manual/platform-specific/iphone/ios-building-and-delivering/build-process.md). Every Unity iOS Xcode project has the following [structure](/engine/6000.3/manual/platform-specific/iphone/ios-introducing/structure-of-xcode-project.md): * A library part in the **UnityFramework** target that includes source (including `UnityFramework/UnityFramework.h`), plug-ins, and dependent frameworks. Building this target in Xcode produces the `UnityFramework.framework` bundle. Unity doesn't place a prebuilt `.framework` in the export folder. * A thin launcher part in the **Unity-iPhone** target that includes app representation data and runs the library. The **Unity-iPhone** target has a single dependency on the **UnityFramework** target. To integrate Unity into another Xcode project, combine both Xcode projects (the native one and the one Unity generates) into a single Xcode workspace, and add the built `UnityFramework.framework` to **Frameworks, Libraries, and Embedded Content** (or **Embedded Binaries**) for your native application's target. Once you do this, you can use the `UnityFramework` class to control the Unity runtime. This [repository](https://github.com/Unity-Technologies/uaal-example/blob/master/docs/ios.md) contains example Projects and plug-ins that demonstrate how to integrate Unity into an Xcode project, along with further documentation. ## UnityFramework class After you load `UnityFramework.framework` in the host app, control the Unity runtime through the `UnityFramework` Objective-C class. The class is declared in `UnityFramework/UnityFramework.h` and is the principal class of the framework bundle: | **Method** | **Description** | | -------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `+ (UnityFramework*)getInstance;` | Singleton class method that returns an instance to `UnityFramework`. | | `- (UnityAppController*)appController;` | Returns the `UnityAppController` subclass of `UIApplicationDelegate`. This is the root Unity class on the native side, and can access the app's View-related objects, such as `UIView`, `UIViewControllers`, `CADisplayLink`, or `DisplayConnection`. | | `- (void)setDataBundleId:(const char*)bundleId;` | Sets the Bundle where the Unity runtime should look for the *Data* folder. For more information, see documentation on the [Data folder](/engine/6000.3/manual/platform-specific/iphone/ios-introducing/structure-of-xcode-project.md). Call this method before calling `runUIApplicationMainWithArgc` or `runEmbeddedWithArgc`. | | `- (void)runUIApplicationMainWithArgc:(int)argc argv:(char*[])argv;` | The default way to run Unity from the main method where there are no other Views. | | `- (void)runEmbeddedWithArgc:(int)argc argv:(char*[])argv appLaunchOpts:(NSDictionary*)appLaunchOpts;` | Call this method when you need to run Unity when other Views exist. | | `- (void)unloadApplication;` | Call this to unload Unity and receive a callback to `UnityFrameworkListener` after the unload completes. Unity will release most of the memory it occupies, but not all of it. You will be able to run Unity again. | | `- (void)registerFrameworkListener:(id)obj;` | Register the listener object that receives callbacks of UnityFramework lifecycle-related events. | | `- (void)unregisterFrameworkListener:(id)obj;` | Unregister a listener object. | | `- (void)showUnityWindow;` | Call this method while a non-Unity View is showing to also show a Unity View that's already running. | | `- (void)pause:(bool)pause;` | Pause Unity. | | `- (void)setExecuteHeader:(const MachHeader*)header;` | You must call this before running Unity in order for CrashReporter to work properly. | | `- (void)sendMessageToGOWithName:(const char*)goName functionName:(const char*)name message:(const char*)msg;` | This method is a proxy to [UnitySendMessage](/engine/6000.3/manual/platform-specific/iphone/ios-developing/plugins-for-ios.md). It finds a game object by name and calls functionName with a single-string message parameter. | | `(void)quitApplication:(int)exitCode;` | Call this to unload Unity completely and receive a callback to `UnityFrameworkListener` when Unity quits. Unity will release all memory.**Note:** You won’t be able to run Unity again in the same process after this call. You can set `quitHandler` on `AppController` to override the default process kill. | ## Limitations Unity doesn't control the runtime lifecycle, so Unity as a Library might not work for all possible use cases. Known limitations include: * Unity as a Library only supports full-screen rendering, and doesn't support rendering on part of the screen. * You can't load more than one instance of the Unity runtime. * You might need to adapt third-party plug-ins (both [native](/engine/6000.3/manual/scripting/compilation-and-code-reload/plug-ins/native.md) and [managed](/engine/6000.3/manual/scripting/compilation-and-code-reload/plug-ins/managed.md)) to work with the Unity runtime. * You can't adjust the device’s status bar visibility through the [iOS Player settings](/engine/6000.3/manual/platform-specific/iphone/getting-started/class-player-settings-ios.md#Status) when using Unity as a Library in a native iOS application. Consider using either of the following options to achieve the same: * Set [`UIStatusBarHidden`](https://developer.apple.com/documentation/bundleresources/information_property_list/uistatusbarhidden?language=objc) or [`UIViewControllerBasedStatusBarAppearance`](https://developer.apple.com/documentation/bundleresources/information_property_list/uiviewcontrollerbasedstatusbarappearance?language=objc) key in the info.plist file of your project. * Set the view controller property [`prefersStatusBarHidden`](https://developer.apple.com/documentation/swiftui/uihostingcontroller/prefersstatusbarhidden/) and call [`setNeedsStatusBarAppearanceUpdate`](https://developer.apple.com/documentation/uikit/uiviewcontroller/1621354-setneedsstatusbarappearanceupdat?language=objc) method. * Set the view controller property [`childViewControllerForStatusBarHidden`](https://developer.apple.com/documentation/uikit/uiviewcontroller/1621451-childviewcontrollerforstatusbarh?language=objc).