From what I see, it looks like this still uses the same kernel that's running on the phone. Thus you can't do anything but a Linux system, since that's what Android runs.
"Android Open Source Project-based Maru provides you Android Lollipop for your smartphone and includes a Debian Linux within an LXC Linux Container for the desktop environment"
"Android Open Source Project-based Maru provides you Android Lollipop for your smartphone and includes a Debian Linux within an LXC Linux Container for the desktop environment"