So musical notation: the first grid pattern in Western culture-- but it does lock us in in interesting ways that we may-- you perhaps have never considered-- compared to how music is made in other cultures.
It's not clear why Sprint would've decided to kill it off, because all that's left is a gimped lock screen (with the option of using Android's regular patternlock).
Kobo's diamond pattern reappears on the Vox's lock screen, which also contains a rotating selection of quotes from authors -- an immediate reminder that, at its heart, the Vox is a reading device.