AAAppDelegate.m

//
//  AAAppDelegate.m

#import "AAAppDelegate.h"
#import <Pushwoosh/PushNotificationManager.h>

@interface MMAppDelegate ()

@end

@implementation MMAppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];    


    // Pushwoosh
    NSString* pushwooshAppCode;
    pushwooshAppCode = @"...";
    
    [PushNotificationManager initializeWithAppCode:pushwooshAppCode appName:@"..."];
    // set custom delegate for push handling
    [PushNotificationManager pushManager].delegate = self;
    
    // handling push on app start
    [[PushNotificationManager pushManager] handlePushReceived:launchOptions];

    // make sure we count app open in Pushwoosh stats
    [[PushNotificationManager pushManager] sendAppOpen];
    
    // don't show push notifications when app is open
    [PushNotificationManager pushManager].showPushnotificationAlert = NO;
    
    [[PushNotificationManager pushManager] registerForPushNotifications];
    
    return YES;
}


#pragma mark -
#pragma mark    Push notifications
#pragma mark -

- (void)application:(UIApplication *)application didRegisterUserNotificationSettings:(UIUserNotificationSettings *)notificationSettings;
{
    [[UIApplication sharedApplication] registerForRemoteNotifications];
}

- (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken;
{  
    // Pushwoosh
    [[PushNotificationManager pushManager] handlePushRegistration:deviceToken];
}

- (void)application:(UIApplication *)application didFailToRegisterForRemoteNotificationsWithError:(NSError *)error;
{    
    // Pushwoosh
    [[PushNotificationManager pushManager] handlePushRegistrationFailure:error];
}

- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo;
{
    // Pushwoosh
    [[PushNotificationManager pushManager] handlePushReceived:userInfo];
}

#pragma mark -
#pragma mark    Pushwoosh
#pragma mark -

- (void) onPushAccepted:(PushNotificationManager *)pushManager withNotification:(NSDictionary *)pushNotification onStart:(BOOL)onStart {
    
    // do nothing when application was already active
    if (!onStart) {
        return;
    }
    
    if (pushNotification[@"u"]) {
        NSData *pushData = [pushNotification[@"u"] dataUsingEncoding:NSUTF8StringEncoding];
        NSDictionary *pushInformation = [NSJSONSerialization JSONObjectWithData: pushData options:NSJSONReadingMutableContainers error:nil];
        
        //work with information
    }
    
    // reset batch number to 0
    [UIApplication sharedApplication].applicationIconBadgeNumber = 0;
}

@end

You don't need this line:

    - (void)application:(UIApplication *)application didRegisterUserNotificationSettings:(UIUserNotificationSettings *)notificationSettings;
    {
        [[UIApplication sharedApplication] registerForRemoteNotifications];
    }