NSAttributedString

// 文字色＆フォント指定
NSDictionary *stringAttributes = @{NSForegroundColorAttributeName: [UIColor blueColor],
NSFontAttributeName: [UIFont systemFontOfSize:14.0f]};
NSAttributedString *string = [[NSAttributedString alloc] initWithString:@"0123" attributes:stringAttributes];
label.attributedText = string;