In May 2007 I showed a chart of dual-mode phone certifications by time. Certifications have continued to grow since then, as the updated graph below shows. These numbers are pretty raw, for example six certifications in November 2006 were for variations on a Motorola phone first certified in October. If you go back and look at the previous chart you will also notice discrepancies in the number of certifications for any particular month. These are presumably because of revisions at the WFA website.
From 2006 to 2007 smartphone certifications were essentially flat, going from 33 to 36, while feature phone certifications went from 11 to 21. These add up to 44 dual mode phone certifications in 2006 and 57 in 2007.
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