Comscore mobile data published on Techcrunch this morning ostensibly shows that one third of US phone subs have a smartphone (73m out of 234m), but when you look at the operating system I would argue that one sixth is a better estimate. I say that because Android and iOS give their users a qualitatively different experience to the other OS’s, largely down to the quality of their browsers and the vibrancy of their app ecosystems. There are arguments that some of the other systems are improving and Blackberry and others are now using the webkit browser, but as a first order approximation at least it is better to think of the smartphone universe as being limited to Android and iOS and therefore about half of the 73m are available as addressable market for smartphone dependent services and apps.
Every cloud has a silver lining though, and the good news here is that if true smartphones have only penetrated one sixth of the market there is still an awful lot of growth left to come. I expect that penetration to increase rapidly with persistent rumours of $100-150 Android devices coming in the near future.
The other interesting thing to note from this data is that Android is now clearly in front of all the others and the gap to second placed iOS is increasing.