How To Improve Your Mobile Site Performance With W3C Navigation API

"As web sites become more like applications, measuring and tuning their performance dramatically increases in importance, especially on mobile devices where latency and other performance-related factors have a high impact on user satisfaction."

The time it takes to load a web page, especially on a mobile phone, plays a big role in whether visitors continue to return to your site or not.  If your load times are too long, visitors will get frustrated and move on to faster loading sites.  Optimizing your site's load time will go a long way toward making sure people keep coming back.  

In order to ensure websites are optimized, Microsoft is providing developers with the W3C Navigation API in Windows Phone 7.5 Mango.  A couple of measurements the W3C API provides data for include: 

Time needed to unload previous page

Time elapsed to look up a page's domain

The time points at which the page DOM starts to load and then becomes interactive

Time required to perform the window.onload event

Total time required to load a page from initial navigation request

If you are coding your mobile site and want to optimize for IE9 on Windows Phone, make sure to take a look at the blog post at the Windows Team Blog.