Not really a feature, but I found it very useful. (I have the white Z2, not sure if this work with the black z2)
I'm waiting on my magnetic charger, so until then, I have been using the micro usb cable to charge my phone.
When I'm ready to go to bed and charge my phone, I'm usually in my room with no light. If you open the flap for the micro usb port, the LCD screen gives off some light inside that port area. It's enough to guide the charging cable in without guessing which way it need to go.
Double tap is pretty awesome though.