iPhone browser tag and optimized web site

What is iPhone's browser tag and how iPhone optimized web site is different from a usual mobile web site?

Thanks!

From stackoverflow sergeb

• Nettuts has a great introduction to web-developement for iPhone. You find it here

  This is the specific code you asked for (taken from that article):

  <!--#if expr="(${HTTP_USER_AGENT} = /iPhone/)"-->   
  
  <!--  
  place iPhone code in here  
  -->   
  
  <!--#else -->   
  
  <!--  
      place standard code to be used by non iphone browser.   
  -->   
  <!--#endif -->
  

  From Espenhh

• Apple defines the user agent here.

  This field is transmitted in the HTTP headers under the key "User-Agent"

  From Jason Cohen

• Apple has some excellent guidelines for iPhone web page development here:

  Safari Web Content Guide for iPhone

  From my brief reading of it, here are a key elements to look out for:

  • The way the "viewport" and scrolling works is a bit different due to the small screen size. There are custom META tags that let you adjust this automatically when someone comes to your page.
  • Beware pages that use framesets or other features that require the user to scroll different elements on the page, because the iPhone does not display scrollbars.
  • If you expect people to bookmark your page on the iPhone, there's a custom META tag that lets you specify a 53x53 icon that will look nicer than the typical favorite.ico.
  • Avoid javascript that depends on mouse movement or hover actions to make things happen, they won't work right on iPhone.
  • There are some custom CSS properties that allow you to adjust text size and highlight color of hyperlinks on the iPhone.
  • There are other key HTML/Javascript features that they tell you to either favor or avoid as well.
  From Tim Farley

• Better Solution:

  *
  
    (NSString *)flattenHTML:(NSString *)html {
  
    NSScanner *theScanner; NSString *text = nil;
  
    theScanner = [NSScanner scannerWithString:html];
  
    while ([theScanner isAtEnd] == NO) {
  
    // find start of tag
    [theScanner scanUpToString:@"<" intoString:NULL] ; 
  
  
    // find end of tag
    [theScanner scanUpToString:@">" intoString:&text] ;
  
  
    // replace the found tag with a space
    //(you can filter multi-spaces out later if you wish)
    html = [html stringByReplacingOccurrencesOfString:
                       [ NSString stringWithFormat:@"%@>", text]
                 withString:@" "];
  
    } // while //
  
    return html;
  

  }

  From Jimit