Kantar has tweeted some numbers which they call App Store Satisfaction results for the various smartphone operating systems in UK.
It shows that lack of apps is still a significant issue for Windows Phone, with App Store Satisfaction sitting at 50%. Unfortunately we do not know if these numbers mean users are 50% satisfied with the store, or 50% of users are satisfied with the store, but presumable Kantar will release more detailed information eventually.
The numbers show iOS leading at 85%, Android next at 70%, Windows Phone at 50% and Blackberry at 42%.
I suspect however that the numbers for Windows Phone will have improved dramatically by 2014, with numerous foundational apps such as banking apps set to arrive over the next few months. Unfortunately the situation around games remains in too much flux, but recent announcements such as the Unity 4.2 engine for Windows Phone and of course the increased market share of the OS will hopefully help to close that gap.
Of course it must be remembered that satisfaction with the app store does not equate directly with satisfaction with the handsets and operating systems themselves, where Windows Phone traditionally scores very high, and often higher than iOS.