matsui-san has written a new blog post on ke-tai.org, describing KEITAIALL, a service for viewing technical specs for Japanese mobile phones.  I'm a fan of the site's simple and clean design, that allows you to view information about handsets at a glance, or search for a specific model.

The information provided includes:

• Carrier
• Model Name
• Manufacturer
• Sale Name
• Series
• First Day of Sale
• Browser Version
• Generation (2G/3G)
• Cache
• Screen Width
• Flash Version
• Ranking According to Share

matsui-san ponders about the licensing of this data, and points out that you can view all the data in xml by visiting http://keitaiall.jp/inc/choice.xml.  If developers are free to use and adapt this data as they choose, it could be a great boon to developers.

Betrend has released a report on mobile access in Japan based on accesses to their mobile platform for the month of October 2009.  The results of the report follow.

Access by carrier

Handset Capabilities

Top handsets by carrier

docomo

au

SoftBank

In the past, a mobile site had to be built using carrier-specific markup to properly function for that carrier. However, now it is possible to use XHTML to build a cross-carrier site, as all Japanese 3G handsets support some form of it [1]. Unfortunately, it is not the same dialect of XHTML: Docomo use i-mode xhtml (based on XHTML mobile profile), au uses XHTML basic, and SoftBank uses XHTML Mobile Profile 1.2. Nevertheless, although there are some differences between these versions, they all share a common base, making it possible to make a site that will function more or less the same across all carriers.

Given that not all handsets support XHTML, if you were to build a mobile site using XHTML, what percentage of handsets would it support? I've scoured the web for the answer to this question, but haven't been able to directly find the answer anywhere. However, as the number of handsets subscribing to 3G vs 2G plans are available, if we assume a handset supports XHTML if and only if it is 3G, we can use these numbers to find the answer.

In total, over 95% of Japanese handsets natively support some form of XHTML. Almost all au handsets support XHTML natively and furthermore the au gateway handles conversion of XHTML to HDML (the markup that older au handsets used). As SoftBank will discontinue its 2G service on March 31, 2010, current subscribers will need to migrate to the 3G service (and handsets that support XHTML). Finally, although Docomo has, relative to the other carriers, a large number of handsets that are not XHTML compatible, Docomo claims that i-mode HTML (which older Docomo handsets use), and i-mode XHTML is mostly compatible. Therefore, I would suggest that if you are building a site for the Japanese market, you do so using XHTML.

[1] Although many Japanese web sites say this is the case, it does not appear to be technically true.  According to Docomo, handsets from the FOMA  2051V, 2002, and 2001series do not support XHTML.  However, we can assume these handsets are few enough to make this generalization.

• Basic JavaScript support (based ECMA-262)
• External CSS
• Cookies and Referer header
• Copy and Paste within the browser
• Multi-window function
• Increased page size from 100KB to 500KB
• BMP and PNG support

Of particular interest to mobile web developers will be the external CSS and cookie support (rumors about this were mentioned previously).  The lack of these have caused developers headaches, as while SoftBank and au support them, docomo did not.  It will be some time before developers can assume all Japanese mobiles support external CSS and cookies, but it is good to see that we are moving in that direction.

Once more concrete details come out, we'll follow up on this story.

There is a rumour going around that new docomo handsets will support cookies and send referrers.  Kimura.Memo has an article stating that he has received a request from a docomo user agent using a docomo IP address that sent the headers HTTP_COOKIE and HTTP_REFERER¹.  This means it is potentially an actual handset, however it could also be some sort of test on docomo's part.

In the past, docomo's handsets have not supported cookies.  This has meant for a site to support sessions, a session id parameter had to be added to URLs.  As the other major carriers, au and SoftBank, support cookies, this has caused developers some pain.  However, if docomo's handsets will support cookies, this will make things easier. 

Whether docomo's new handsets will actually support cookies remains to be seen.  If only new handsets support cookies, this will probably change little in the short term, as most docomo handsets will still not support them, and developers will thus need to design for the old handsets as well.  However, it would be a step in the right direction, and mean in the future, developers could start assuming all handsets support cookies, much like they are now doing with XHTML support.

Footnotes

1.  An interesting side note is that referred is misspelled in the header, HTTP_REFERER.

docomo will launch a social network like service, docomo community (ドコモコミュニティ),  on March 2, 2009.  The service bills itself as a way to share photos and journal entries between friends and family members, and seems especially targeted at sharing between children and parents.  This is shrewd marketing on the part of docomo, who along with SoftBank and au introduced content filtering earlier this year, blocking sites in categories including SNS for all users under 18.  Perhaps in part to preempt others from crying foul, the site will not have any user search feature and to add a "friend" will require a user to input the other user's i-mode email address.  The service itself will be free (though normal packet charges apply), and be limited to users with FOMA handsets and above (non docomo handsets will not be supported).

(Hat tip: matsuiさん)