I'm not sure these pages really offer evidence one way or the other, but I do agree my anecdote shouldn't be taken as gospel.
Regarding your second link specifically I know lots of folks who stick to using LTE on their Android devices instead of their wifi because LTE is often faster than their home internet, so I'm not sure that showing Android phones are less likely to use WiFi really means anything.
>I know lots of folks who stick to using LTE on their Android devices instead of their wifi
Actually Akamai research confirmed that Android and iPhone are neck to neck for cellular traffic. Because of the iPad wifi traffic for iOS is more than Android but that may change with the release of Nexus 7.
