Ok, guys - I finally figured this out (it was driving me crazy)! As I guessed earlier, the only way to get the Tablet/Phone Mode option is to install an older phone-mode only version (I used 1.9.9) and the upgrade to the latest version. As soon as I did that, the Tablet/Phone mode option appeared in the settings...
I guess they wanted to provide existing phone-mode-only users the option to revert back to that mode if they wish, but new installs were forced to use the tablet version...
So, if you really want the option, remove the latest version, install 1.9.9 (it's posted in this thread) and then upgrade to the latest version.
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