I don't have any numbers, but my gut feel would rank them like this:
1. WAP
2. J2ME
3. BREW
4. Symbian
Certainly there are more WAP compatible devices out there than any of the other technologies. You probably can't find a J2ME, BREW, or Symbian device that doesn't also have a browser with support for some version of WAP.
Next I'd say J2ME for sure. Again, you probably can't find a Symbian device that doesn't at least have an installable JVM. The same is true for BREW although most BREW devices don't let you install your own applications so it's kind of moot.
After that it gets fuzzy for me. Certainly in the US, BREW devices far out number Symbian devices. Almost all phones currently available from Sprint and Verizon are BREW devices. Sprint doesn't allow you to install 3rd party BREW apps and they don't advertise the handsets as being BREW phones but inside, it's all BREW.
The exceptions would be the few Windows and Palm devices offered by the CDMA carriers.
I'll warn you up front that these market shares probably have very little bearing on what platform you'd choose to launch a product or service. The cooperation of the carrier is probably the biggest factor. Next, you have to consider the technological limitations. There may be more
Java phones out there but Symbian and BREW offer much greater capabilities and speed. Then you have to consider distribution methods. BREW and the BDS are a well oiled, money making machine. It's much tougher to make a buck selling Java apps.
William Frantz
http://sprintdevelopers.com [ October 26, 2005: Message edited by: William Frantz ]