YotaPhone 2
The story of two people UX concepting two screens.
The two-screen YotaPhone 2, called by Engadget 'one of the quirkiest smartphones', had a lot of teams work on the UI.

No wonder: when one of the two screens is used, the other becomes invisible and inaccessible. This causes some serious mental idiosyncrasy in most UI designers—me and Niko included.
Our original concept (on the left) had a variable tab-based top part. As I write this, Android implemented the same idea using 'permanent notifications'. Yota Devices (on the right) in the final releases used our logic of widgets, the permanent notifications (dubbed 'control bar') and some other elements—but redesigned them.
Jorjeputo, as he was creative directing YotaPhone 2, had to pick and choose the best ideas from all concepts. Ours contributed the locking/unlocking mechanism, not exactly a no-brainer for a two-screen phone, and many dashboard principles.
For those of you interested, our typical UI report is 60 to 200 pages, almost a book. In this one, both copy and layout are by yours truly.
I was so tired doing version after version of the locking-unlocking diagrams, I finally wrote a script for this. We called this concept BUS—Better Unlocking System. As far as I understand, it has been implemented in full.
Below are different visual languages we proposed. None have been accepted. My favourite, to this day, is the last one, dubbed 'retro'. I hope to make something out of it one day.
Reviewers seemed to enjoy the UI. For this device, the principle point of criticism was price and responsiveness, not the interface.
"It's ridiculously easy to make it feel like it's my own, special device."
"I found the always on screen useful, with vital information popping into view without me having to even touch the handset."
"You can reply to texts, tweet, browse your calendar, initiate a call and more. These feed off their Android counterparts, so you don't have two different inboxes for texts; that inbox is just presented differently in native YotaPanel form."