[mac01021]

Does this come with the same gnome 3 that I would install on a desktop?

Can I make apps that look consistent with the rest of the phone's OS just by using GTK?

[solarkraft]

No and kind of.

It ships with a custom Wayland compositor built with GNOME technology, but theoretically you could install GNOME. They have a custom widget library, but that builds on GTK.