IOS App Integrate Google Map Problems and Method to solve them

1. You must get a key in google developer center, and register it in below function in AppDelegate.m file.

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

    // Override point for customization after application launch.

    [GMSServices provideAPIKey:@"AIzaSyD4UCHJbsoJMjnrQN_ii6ueJjJ84kzUpnc"];

 }

2. If during start up google map have below error in debug window, need to add -ObjC to Build Settings -> Linking -> Other Linker Flags.

2015-10-24 22:56:31.761 EasyQ[2510:176045] CoreData: Failed to load optimized model at path '/Users/Yanliyuan/Library/Developer/CoreSimulator/Devices/DFA41111-C50F-4C9B-8D01-DAD0F38BC6B9/data/Containers/Bundle/Application/9A82A689-5B32-4828-B54A-55112EB8BE17/EasyQ.app/GoogleMaps.bundle/GMSCacheStorage.momd/Storage.omo'

2015-10-24 22:56:31.788 EasyQ[2510:176045] CoreData: Failed to load optimized model at path '/Users/Yanliyuan/Library/Developer/CoreSimulator/Devices/DFA41111-C50F-4C9B-8D01-DAD0F38BC6B9/data/Containers/Bundle/Application/9A82A689-5B32-4828-B54A-55112EB8BE17/EasyQ.app/GoogleMaps.bundle/GMSCacheStorage.momd/Storage.omo'

2015-10-24 22:56:31.805 EasyQ[2510:176045] CoreData: Failed to load optimized model at path '/Users/Yanliyuan/Library/Developer/CoreSimulator/Devices/DFA41111-C50F-4C9B-8D01-DAD0F38BC6B9/data/Containers/Bundle/Application/9A82A689-5B32-4828-B54A-55112EB8BE17/EasyQ.app/GoogleMaps.bundle/GMSCacheStorage.momd/Storage.omo'

2015-10-24 22:56:31.816 EasyQ[2510:176045] CoreData: Failed to load optimized model at path '/Users/Yanliyuan/Library/Developer/CoreSimulator/Devices/DFA41111-C50F-4C9B-8D01-DAD0F38BC6B9/data/Containers/Bundle/Application/9A82A689-5B32-4828-B54A-55112EB8BE17/EasyQ.app/GoogleMaps.bundle/GMSCacheStorage.momd/Storage.omo'

2015-10-24 22:56:31.842 EasyQ[2510:176045] -[GMSMapView animateToCameraPosition:]: unrecognized selector sent to instance 0x7fd3727282f0

2015-10-24 22:56:31.875 EasyQ[2510:176045] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[GMSMapView animateToCameraPosition:]: unrecognized selector sent to instance 0x7fd3727282f0'