ayephoner
macrumors 6502a
https://www.gsmarena.com/nubia_x_flash_sale_100_thousand_devices-news-34057.phpWas it successful
This is all I found through an extensive 1 minute search. I don't remember hearing much about it, but knew I heard of this idea happening before. I actually just remembered, it was the YotaPhone 2 that I was thinking of. It had an e-ink screen on the back, which I think is pretty awesome.
https://www.cnet.com/reviews/yotaphone-2-review/