Updating Google sitemap for mobile

Question

I have a series of utilities to generate Google sitemaps for my whole site. These files are massive, and slow to build. We want to start telling Google these pages are mobile-crawl-able too, by adding them to mobile sitemaps, but the documentation is unclear if I need to specify physically different files for my mobile URLs than for my normal ones.

If this is my current sitemap:

<?xml version="1.0" encoding="UTF-8" ?>
 <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
    <url>
        <loc>http://mobile.example.com/article100.html</loc>
    </url>
</urlset>

Can I simply change it to:

<?xml version="1.0" encoding="UTF-8" ?>
 <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
  xmlns:mobile="http://www.google.com/schemas/sitemap-mobile/1.0">
    <url>
        <loc>http://mobile.example.com/article100.html</loc>
        <mobile:mobile/>
    </url>
</urlset>

Or do I need to create new files with the additional markup, alongside my existing files?

Answer 1

Per default (if I recall correctly) Google will assume that normal pages are also relevant to later smart phones. Mobile sitemaps are then to let Google know of pages that also work on older mobiles. In real-life though, if you have designed mobile-friendly-layout pages, you might still want to create a mobile sitemap for them.

I suggest you try a sitemap generator that can create mobile sitemaps and then duplicate what they do (assuming you don't want to use a sitemapper to create mobile sitemaps)

Answer 2

Google's mobile Sitemap documentation says:

"A Mobile Sitemap can contain only URLs that serve mobile web content. Any URLs that serve only non-mobile web content will be ignored by the Google crawling mechanisms. If you have non-mobile content, create a separate Sitemap for those URLs."

So you need one Sitemap for your desktop content, and another for your mobile content.