- There is a nearly infinite range of device sizes and capabilities. This is adding a great deal to the complexity of publishing a site for the mobile web.
- Correct annotations communicate a relationship between a desktop page and its smartphone-optimized equivalent. Knowing this relationship allows Google’s algorithms to handle both URLs correctly.
- The HTTP Vary: User-agent header helps caches to not show a desktop user-agent a cached smartphone page, and vice versa, and it’s a signal that Googlebot-Mobile for smartphones should crawl this page.
- Responsive Web Design can be implemented in a way where the full content of the page does not need to be downloaded to a mobile device. There are many options and considerations that apply to each page and webmasters need to figure out what optimizations are best for their content.
- While thinking about what a mobile device downloads, also consider how it gets downloaded and rendered.
- RWD does come with the baggage of the full content being delivered to the device and the screen size optimizations being performed client-side.
- There is plenty of evidence that searchers use smartphones to do tasks that webmasters have historically considered “desktop only”, and do so in locations where a desktop with a broadband connection is available such as at home or work.
- Consider the technologies used on your pages. For example, Flash content is not viewable on a large number of smartphone devices.
- Looking at what different responsive websites do shows that similar websites emphasize different aspects of their pages, and do so differently.
We have all seen that the use of mobile is exploding. Yet publishers have been slow to fully optimize their sites for this new web experience.
One thing Pierre pointed out to me is that people get confused about what mobile refers to. Historically it used to mean what we now call “feature phones”. Ironically, in my view, these are the phones without features! They usually have very small screen sizes and numeric only keypads.
Nowadays this definition includes smartphones, with their larger screen sizes and more complete keyboard capabilities. For many, the definition also includes tablets as these devices are meant to be carried with you. Google itself has blurred this definition a bit with their Enhanced Campaigns for AdWords, which lumps tablets together with desktops.
“In addition, we keep seeing new devices which are oversized smartphones, and other new devices which are smaller and smaller tablets. As a result, we have a nearly infinite range of device sizes and capabilities.”
In addition, we keep seeing new devices which are oversized smartphones, and other new devices which are smaller and smaller tablets. As a result, we have a nearly infinite range of device sizes and capabilities. This is adding a great deal to the complexity of publishing a site for the mobile web.
Pierre Far is one of Google's experts on the mobile web so I sent him some questions by email to get his take on how publishers should approach these new challenges.
Eric Enge: What are the best practices for tagging desktop pages and mobile pages in a mobile sub-domain architecture?
Pierre Far: We support three configurations for smartphone-optimized websites. Having a separate site on subdomains is one type of separate URLs setup and the annotations are explained in our recommendations site.
Notes from Eric: From the above listed link, here is a look at the basic annotations recommended by Google:
If the desktop page URL is http://www.example.com/page-1, than the rel alternate tag on the desktop page should point to: http://m.example.com/page-1.
If the mobile page URL is http://www.example.com/page-1, than the rel canonical tag on the mobile page should point to: http://www.example.com/page-1.
You can also note the presence of the two versions of the page in your XML Sitemaps file: