- Use multiple UILabel and each contains different font style.
 - Use HTML tag and UIWebView.
 - Use NSMutableAttributedString, this classe is added in iOS from 3.2, it needs Core Text to render rich text on the view. AliSoftware created a useful classe UIAttributedLabel which is an UILabel's subclass and supports NSMutableAttributedString. Check AliSoftware's github for more information.