Simply to get User uploaded images from Pinterest we need to do following things first:-

1. Install Pinterest native app on iOS device.
2. Get logged in with any user credential.
3. Now Hit the Pinterest API with passing .
4. In json response you will get all images.

-(void)getImages:(id)sender{
    NSURL *url = [NSURL URLWithString:@"https://api.pinterest.com/v3/pidgets/users//pins/"];
    NSData *postData = [@"" dataUsingEncoding:NSUTF8StringEncoding allowLossyConversion:YES];
    NSString *postLength = [NSString stringWithFormat:@"%d", [postData length]];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url cachePolicy:NSURLCacheStorageNotAllowed timeoutInterval:300];
    [request setHTTPMethod:@"GET"];
    [request setValue:postLength forHTTPHeaderField:@"Content-Length"];
    [request setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
    [request setHTTPBody:postData];
    NSError *error = [[NSError alloc] init];
    NSHTTPURLResponse *response = nil;
    NSData *urlData=[NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];

    if (urlData) {
        NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData:urlData options:0 error:nil];
        NSLog(@"%@",jsonArray);
    }


}

Happy Coding :)**