How to call multiple rest api one by one in loop

Question

I am trying get data from server to store locally when needed. The data is present at different api urls. I want to call all those apis on a single refresh click.Kindly help me to solve this.

-(void) call:(NSString *)url{

            NSURLRequest *Request1 = [NSURLRequest requestWithURL :[NSURL URLWithString:url] cachePolicy:NSURLRequestReloadIgnoringCacheData timeoutInterval:30.0];
            // calling only one api
            NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:Request1 delegate:self startImmediately:YES];
            //            flag = true;
            [SVProgressHUD showWithStatus:@"Wait while we fetch data .."];
            if (connection){
                NSLog(@"connection success");
            }
            else{
                // handle error here
            }

}