ZTE's plans for this year's Mobile World Congress just got a little more interesting. While we've already taken a look at the huge Grand Memo in action, the Chinese maker's invite suggests that there will be another "major new mobile device" to show us, throwing in a 'ZTEMozilla' hashtag for good measure. We knew that Mozilla and ZTE have been holding hands for a while, and this serves to confirm mutterings that we'd see some Firefox OS hardware early this year -- although there's no hint of that mysterious European carrier just yet. Hold on, Barcelona. We're coming.