title: App Crashes when ReloadData done for the tableView
body: <p>I am using the following code to reload my tableView when its done adding all the data to my Mutable Arrays, but the app always crashes</p>
  
  <pre><code>   - (void)viewDidLoad
  {
      [super viewDidLoad];
  
      // Do any additional setup after loading the view.
  
      //Spinner Add while waiting
      UIActivityIndicatorView *spinner = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
      spinner.frame = CGRectMake(147, 10, 25, 25);
      [self.tableView addSubview:spinner];
      [spinner startAnimating];
  
      operationQueue = [[NSOperationQueue alloc] init];
  
      usersFirstName = [[NSMutableArray alloc] init];
      usersLastName = [[NSMutableArray alloc] init];
      usersAvatar = [[NSMutableArray alloc] init];
  
      NSString *urlstring = [NSString stringWithFormat:@"https://www.test.com/scribble/%@/",scribbleId];
      NSURL *url = [NSURL URLWithString:urlstring];
      NSURLRequest *request = [NSURLRequest requestWithURL:url];
      AFJSONRequestOperation *operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:request success:^(NSURLRequest *request, NSHTTPURLResponse *response, id JSON){
          users = JSON[@"users_favored"];
          if (users.count &gt; 0) {
              NSUInteger count = [users count];
              for (NSUInteger i =0; i&lt;count; i++) {
                  NSString *urlString = [NSString stringWithFormat:@"https://www.test.com%@",[users objectAtIndex:i]];
                  NSURL *url = [NSURL URLWithString:urlString];
                  NSURLRequest *requestUser = [NSURLRequest requestWithURL:url];
                  AFJSONRequestOperation *operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:requestUser success:^(NSURLRequest *request, NSHTTPURLResponse *response, id JSON){
                      if (i == 0) {
                          usersFirstName = [JSON[@"first_name"] mutableCopy];
                          usersLastName = [JSON[@"last_name"] mutableCopy];
                          usersAvatar = [JSON[@"user_avatar"] mutableCopy];
                      }else{
                          [usersFirstName addObjectsFromArray:JSON[@"first_name"]];
                          [usersLastName addObjectsFromArray:JSON[@"last_name"]];
                          [usersAvatar addObjectsFromArray:JSON[@"user_avatar"]];
                      }
                      if (i == count-1) {
                          [self.tableView reloadData];
                          [spinner stopAnimating];
                          [spinner removeFromSuperview];
                      }
                  }failure:nil];
                  [operationQueue addOperation:operation];
              }
          }else{
              self.navigationItem.title = @"No Favors";
              [spinner stopAnimating];
              [spinner removeFromSuperview];
          }
      } failure:nil];
      [operationQueue addOperation:operation];
  
  }
  
  - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
  {
      // Return the number of sections.
      return 1;
  }
  
  - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
  {
      return usersFirstName.count;
  }
  
  - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
  {
      static NSString *simpleTableFavorIdentifier = @"FavorCell";
  
      UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:simpleTableFavorIdentifier];
  
      if (cell == nil){
          cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:simpleTableFavorIdentifier];
      }
  
      NSString *firstName = [usersFirstName objectAtIndex:indexPath.row];
      NSString *lastName = [usersLastName objectAtIndex:indexPath.row];
      NSString *avatar = [usersAvatar objectAtIndex:indexPath.row];
      NSString *userFullName = [NSString stringWithFormat:@"%@ %@",firstName,lastName];
      UIImageView *userAvatar = (UIImageView *)[cell viewWithTag:100];
      if ([avatar length ] &gt; 0) {
          NSString *img = [@"https://dtest_media_and_assets.s3.amazonaws.com/" stringByAppendingString:avatar];
          [userAvatar setImageWithURL:[NSURL URLWithString:img] placeholderImage:[UIImage imageNamed:@"scribble.png"]];
      }else{
          userAvatar.image = [UIImage imageNamed:@"scribble.png"];
      }
      userAvatar.layer.cornerRadius = 4.0;
      userAvatar.clipsToBounds = YES;
      UILabel *userNameLabel = (UILabel *)[cell viewWithTag:101];
      userNameLabel.text = userFullName;
  
      return cell;
  
  }
  </code></pre>
  
  <p>The error it gives is</p>
  
  <pre><code> 2013-03-15 16:37:08.910 test[19547:c07] -[__NSCFString count]: unrecognized selector sent to instance 0x8679c80
  
  2013-03-15 16:37:08.911 test[19547:c07] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFString count]: unrecognized selector sent to instance 0x8679c80'
  
  *** First throw call stack:
  (0x1cdf012 0x169fe7e 0x1d6a4bd 0x1ccebbc 0x1cce94e 0x143d7 0x7c8548 0x7cb224 0x68f952 0x68f2dc 0x140d7 0x281d2 0x29569 0x2f9553f 0x2fa7014 0x2f977d5 0x1c85af5 0x1c84f44 0x1c84e1b 0x21bb7e3 0x21bb668 0x5e3ffc 0x200d 0x1f35)
  libc++abi.dylib: terminate called throwing an exception
  </code></pre>
  
  <h1>Edit</h1>
  
  <p>everything works just fine when I use this instead</p>
  
  <pre><code>[usersFirstName addObject:JSON[@"first_name"]];
  [usersLastName addObject:JSON[@"last_name"]];
  [usersAvatar addObject:JSON[@"user_avatar"]];
  [self.tableView reloadData];
  if (i == count-1) {
      [spinner stopAnimating];
      [spinner removeFromSuperview];
  }
  </code></pre>