@roadriverrail @djsundog Definitely PalmOS -- and I would love to hear some of your stories about the time spent working on PalmOS. :)
(I used to use the PalmOS "Web Developer" to make phone apps in the seriously beautiful cloud designer circa 2009, or so -- did you work on that?)
My opinion comes from seeing the winners and losers from the 2006-2012 era of phones -- I definitely noticed a trend of "if it launched on CDMA, it was nearly DOA" (PalmOS, the Microsoft Kin, etc.).