iPhone Browser Capabilities and Guidelines

University of Washington's Emerging Technology group published notes from Apple's Developing Web Sites for iPhone session from WWDC last week. The blog entry provides some interesting information for users and web developers alike about the iPhone's capabilities, and has been summarized below.

Apple listed what the iPhone offers for websites:

Removed per Apple's request

A few iPhone size limitations / restrictions are noted in developing for the iPhone:

Removed per Apple's Request

Apple recommends the following design considerations:

Removed per Apple's Request

Apple's iPhone comes out on June 29th, 2007. At WWDC, Apple announced that Web-based applications will be the only way for 3rd party developers to produce applications for the iPhone.- 10MB max html size for web page
- Javascript limited to 5 seconds run time
- Javascript allocations limited to 10MB
- 8 documents maximum loaded on the iPhone due to page view limitations
- Quicktime used for audio and video

- the page view feature lets you look at multiple websites and documents by scrolling thru them one after another
- Full PDF support
- double tap for zoom in
- one finger as a mouse used to
-- pan page
-- press and hold to display the information bubble
- two fingers as a mouse used to
-- pinch content to shrink - zoom out
-- pan page
-- scroll wheel events
- new telephone links allows you to integrate phone calls directly from your webpage. remember this is only on safari.
- built in google maps client for integrated mapping from your website

- separate html and css
- use well structured and valid html
- size images appropriately dont rely on browser scaling
- tile small images in backgrounds, dont use large backgroung images
- iPhone supports both EDGE and WiFi. EDGE pipe is smaller than WIFI pipe so think about bandwidth when developing.
- XHTML mobile documents supported
- stylesheet device width:480px
- apply different css for the iPhone. For example displaying a one column page for iphone vs a 3 column page on a desktop.
- there are no scroll bars or resize knobs. the iphone will automatically expand the content
- Avoid framesets, scrollable frames are automatically expanded to fit the content
- iPhone User Agent: Mozilla/5.0 (iPhone; U; CPU like Mac OS X; en) AppleWebKit/420+ (KHTML, like Gecko) Version/3.0 Mobile/1A538a Safari/419.3
- Video: H.264 baseline profile level 3.0 up to 640480 fps

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