Use following block of code for ios 7+.
NSString *htmlString = @"<h1>Header</h1><h2>Subheader</h2><p>Some <em>text</em></p><img src="http://blogs.babble.com/famecrawler/files/2010/11/mickey_mouse-1097.jpg" width=70 height=100 />";
NSAttributedString *attributedString = [[NSAttributedString alloc]
initWithData: [htmlString dataUsingEncoding:NSUnicodeStringEncoding]
options: @{ NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType }
documentAttributes: nil
error: nil
];
textView.attributedText = attributedString;