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Optimising sites for mobile
Patrick H. Lauke / Droidcon / Berlin / 4 November 2009
TIPS FOR MOBILE AND CROSS-DEVICE WEB DEVELOPMENT
web evangelist at Opera
Opera – one browser on many devices
Mobile web is an uneven landscape:
● Full Web (Android Browser, Opera Mobile, …)● Constrained browsers – WAP, limited standards support, proprietary markup● Proxy-based (Opera Mini, …)● Games consoles / portables
Mobile capabilities also vary:
● Screen size● Input mechanism – touch, keypad, other?● Memory and processing power● Colour palettes● Native font● Connection speed / quality
One Web means making, as far as is reasonable, the same information and services available to users irrespective of the device they are using. However, it does not mean that exactly the same information is available in exactly the same representation across all devices.
W3C Mobile Web Best Practices http://www.w3.org/TR/mobile-bp/#OneWeb
Approaches to mobile web development:
● Do nothing – use standards, defensive design● Separate site (m.mysite.com, mysite.mobi)● Single site, but optimised for cross-device
Server-side detection of mobile:
● “Browser sniffing” the User Agent stringOpera/9.80 (J2ME/MIDP; Opera Mini/5.0.2056/866; U; en) Presto/2.2
● When pattern matching can go wrong...● Offer users a way back (example of Orkut)
Client-side detection of mobile:
● “Browser sniffing” the User Agent string again● “Capability sniffing” reliant on JavaScript● CSS 2.1 Media Types● CSS 3 Media Queries
CSS 2.1 Media Types:
● Print, screen, handheld, projection, tv, …● Partially supported● Lump all devices into single categories
http://www.w3.org/TR/CSS21/media.html
CSS 2.1 Media Types:
<link rel="stylesheet" ... media="print, handheld" href="...">@import url("...") print;@media print { // insert CSS rules here}
CSS 3 Media Queries:
● Build and extend CSS 2.1 Media Types● More granular control of capabilities● width, height, orientation, color, resolution, …
http://www.w3.org/TR/css3-mediaqueries/
CSS 3 Media Queries:
@media screen and (max-device-width: 480px) { // insert CSS rules here
}Demonstration of Media Queries
CSS 3 Media Queries and SVG:
● SVG already resolution independent● Ideal for device interfaces, maps, graphs, …● Combination with CSS 3 Media Queries
Demonstration of Media Queries + SVG
SVG in OBJECT, CSS and IMG element*native inclusion in HTML5?
*only in Opera at the moment
And beyond that?
● Mobile Web Best Practices● Mobile Web Applications Best Practices
http://www.w3.org/TR/mobile-bp/http://www.w3.org/TR/mwabp/
Crossover with accessibility:
● accessibility = extreme usability?● deaf/blind/colourblind/mobility impaired● Mobile Web Best Practices vs WCAG 2.0
http://www.w3.org/TR/mwbp-wcag/
call to arms action
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