We first saw TCL's foldable phone concepts in late February, which were extremely bare bones mock-ups. This is a much more mature prototype.
While the Samsung Galaxy Fold is a large phone that opens into a tablet, TCL envisions a more pocketable flip phone for one of its designs.
This design exhibits a large air gap and something TCL calls its Dragon Hinge, however it's also working on a different style that lays flat.
It looks like a billfold here.
Here are more pictures of foldable concepts before we get to the next prototype.
TCL calls this one the One Piece, because it's made of two pieces of glass fused together into one. Interestingly, there are no buttons and no ports.
You'd have to rely on an in-screen fingerprint reader, pin or face unlock to get in, as well as wireless charging to power it up.
Bone conduction is one way that a buttonless phone could emit sound, though TCL reminds us this is only a rough prototype -- it's something they're thinking about, but haven't solved.
The waterfall display shows off a much more elegant phone with deeply curved sides and a wraparound screen that stops at the edges.
As with its other concept devices, see three rear cameras on this mock-up design.
This midrange device features tools like a rear-mounted fingerprint sensor.
The display can turn standard-def content into high-definition content with built-in software.
The black and white colors also glint in the light.
There's a programmable side key, too.