iOS app启动的方式有哪些：

1. 自己启动（用户手动点击启动）

2. urlscheme启动（关于urlScheme的详解点击打开链接）

3. 本地通知启动 （自己写的本地通知启动，蓝牙模块的启动，地理围栏的启动）

4. 远程通知启动 （后台服务器的推送通知）

在appdelegate.m文件中

系统给的一些关于launchoption的字典里面的内容

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions 

如何判断呢？代码如下：

UIKIT_EXTERN NSString *const UIApplicationLaunchOptionsURLKey                   NS_AVAILABLE_IOS(3_0); // userInfo contains NSURL with launch URL
UIKIT_EXTERN NSString *const UIApplicationLaunchOptionsSourceApplicationKey     NS_AVAILABLE_IOS(3_0); // userInfo contains NSString with launch app bundle ID
UIKIT_EXTERN NSString *const UIApplicationLaunchOptionsRemoteNotificationKey    NS_AVAILABLE_IOS(3_0) __TVOS_PROHIBITED; // userInfo contains NSDictionary with payload
UIKIT_EXTERN NSString *const UIApplicationLaunchOptionsLocalNotificationKey     NS_AVAILABLE_IOS(4_0) __TVOS_PROHIBITED; // userInfo contains a UILocalNotification
UIKIT_EXTERN NSString *const UIApplicationLaunchOptionsAnnotationKey            NS_AVAILABLE_IOS(3_2); // userInfo contains object with annotation property list
UIKIT_EXTERN NSString *const UIApplicationProtectedDataWillBecomeUnavailable    NS_AVAILABLE_IOS(4_0);
UIKIT_EXTERN NSString *const UIApplicationProtectedDataDidBecomeAvailable       NS_AVAILABLE_IOS(4_0);
UIKIT_EXTERN NSString *const UIApplicationLaunchOptionsLocationKey              NS_AVAILABLE_IOS(4_0); // app was launched in response to a CoreLocation event.
UIKIT_EXTERN NSString *const UIApplicationLaunchOptionsNewsstandDownloadsKey    NS_AVAILABLE_IOS(5_0) __TVOS_PROHIBITED; // userInfo contains an NSArray of NKAssetDownload identifiers
UIKIT_EXTERN NSString *const UIApplicationLaunchOptionsBluetoothCentralsKey     NS_AVAILABLE_IOS(7_0); // userInfo contains an NSArray of CBCentralManager restore identifiers
UIKIT_EXTERN NSString *const UIApplicationLaunchOptionsBluetoothPeripheralsKey  NS_AVAILABLE_IOS(7_0); // userInfo contains an NSArray of CBPeripheralManager restore identifiers
UIKIT_EXTERN NSString *const UIApplicationLaunchOptionsShortcutItemKey          NS_AVAILABLE_IOS(9_0) __TVOS_PROHIBITED; // userInfo contains the UIApplicationShortcutItem used to launch the app.
 
// Key in options dict passed to application:[will | did]FinishLaunchingWithOptions and info for UIApplicationDidFinishLaunchingNotification
UIKIT_EXTERN NSString *const UIApplicationLaunchOptionsUserActivityDictionaryKey    NS_AVAILABLE_IOS(8_0); // Sub-Dictionary present in launch options when user activity is present
UIKIT_EXTERN NSString *const UIApplicationLaunchOptionsUserActivityTypeKey          NS_AVAILABLE_IOS(8_0); // Key in user activity dictionary for the activity type
 
UIKIT_EXTERN NSString *const UIApplicationOpenSettingsURLString NS_AVAILABLE_IOS(8_0);
 
// Keys for application:openURL:options:
UIKIT_EXTERN NSString *const UIApplicationOpenURLOptionsSourceApplicationKey NS_AVAILABLE_IOS(9_0);   // value is an NSString containing the bundle ID of the originating application
UIKIT_EXTERN NSString *const UIApplicationOpenURLOptionsAnnotationKey NS_AVAILABLE_IOS(9_0);   // value is a property-list typed object corresponding to what the originating application passed in UIDocumentInteractionController's annotation property
UIKIT_EXTERN NSString *const UIApplicationOpenURLOptionsOpenInPlaceKey NS_AVAILABLE_IOS(9_0);   // value is a bool NSNumber, set to YES if the file needs to be copied before use

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Override point for customization after application launch.
    
    //用户自己点击启动
    if(!launchOptions)
    {
        NSLog(@"用户点击app启动");
    }
    else
    {
        NSURL *url = [launchOptions objectForKey:UIApplicationLaunchOptionsURLKey];
        //app 通过urlscheme启动
        if (url) {
            NSLog(@"app 通过urlscheme启动 url = %@",url);
        }
        UILocalNotification *localNotification = [launchOptions objectForKey:UIApplicationLaunchOptionsLocalNotificationKey];
        //通过本地通知启动
        if(localNotification)
        {
            NSLog(@"app 通过本地通知启动 localNotification = %@",localNotification);
        }
        NSDictionary *remoteCotificationDic = [launchOptions objectForKey:UIApplicationLaunchOptionsRemoteNotificationKey];
        //远程通知启动
        if(remoteCotificationDic)
        {
            NSLog(@"app 通过远程推送通知启动 remoteCotificationDic = %@",remoteCotificationDic);
        }
        
    }
    
    return YES;
}

总结：当launchOptions为空时是用户自己点击app启动，不为空时，要根据相应的key是否存在来判断是通过哪种方式启动的。