When foldable phones first came out five years ago, there were critics who found their fragility and thickness unacceptable. Both problems have been addressed and fixed. Today’s best foldable phones are just a hair thicker than a traditional phone and almost as durable, as shown by half a dozen high-profile “torture tests” conducted by media outlets over the past few years – plus I have anecdotal evidence from years of using and accidentally dropping several foldable phones.

What I am saying is that foldable phone technology is maturing, and now the next big step forward is happening: Tecno has unveiled the prototype of a tri-fold phone – a single 10-inch screen that can be folded at two points (like a Z) into a compact phone shape.

The key word here is “prototype,” as this device, called the Tecno Phantom Ultimate 2, isn’t ready for release yet. But knowing how fast Chinese brands work, I wouldn’t be surprised if it launches within a year. And in fact, there are rumors that Huawei will launch its own tri-fold phone very soon – although Huawei’s device is still completely under wraps except for a few leaks.

Tecno’s tri-fold prototype measures just 11mm when folded, according to Tecno’s press materials. That’s very impressive considering the device stacks three layers of screen on top of each other.

One of the more interesting use cases for a tri-fold phone is that the user can manipulate the hinge angle to put the phone in unique positions, aside from having a larger full-screen when fully extended. For example, provided the hinge is stable enough and the software is optimized, we can use a tri-fold phone like a laptop (as seen in the main photo above) or in a dual-screen device with displays facing both ways.

Tecno’s press materials say that the hinge is rigid enough to stay in place at any angle (like most modern foldable phones), and that the device also supports the use of styluses.

However, since this is just a prototype and hasn’t been revealed to the public yet, we obviously have to take everything with a grain of salt. However, I have tested Tecno’s previous two foldable devices and was impressed with the hardware.

ForbesTecno Phantom V Flip Review: The cheapest foldable phoneFrom Ben Sin

The good news for those of us who are excited about this is that Huawei’s tri-folding phone has already been spotted in public a few times (used by Huawei employees), so it’s not far off from seeing a real tri-folding phone out in the world.