How much usable storage space does the 16Gb Nexus 9 have? How much usable storage space is available on a 16Gb Nexus 9 once the space occupied by the OS, preinstalled software, etc. is subtracted?

Please do not answer with speculation; I am interested in answers with authoritative sources, or from people who have a Nexus 9 and can report directly.

To clarify: I am interested in the space available on a brand new Nexus 9, complete with everything that Google include on it. I remove it from the box, turn it on, and check the available storage. What do I see? :-)
For the 16GB version: 11.05GB Source



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For the 32GB version: 25.61GB



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