The original note, as written at the time
WATER-TIGHT SMARTPHONE. A drawing of a novel smartphone design with a smooth continuous bevelled surface. The surface projects outward to accommodate the audio and battery jack. This protrusion can be bent backwards to be concealed from sight. The receptor tip of this protrusion has a tight removable seal.
Ongoing development
A phone with a smooth, continuous, bevelled surface, where the surface projects outward in one place to house the audio and charging jack — and that protrusion can be bent backwards to be concealed. The receptor tip has a tight removable seal.
The problem being solved is the oldest one in industrial design: a port is a hole, a hole is a failure point, and the failure point is on the face you hold.
Every current answer is a compromise. Remove the port and you lose the ability to charge and listen at once, and you make the device disposable when the battery ages. Keep the port and the device is not really sealed, whatever the rating says, and the seal degrades with every insertion.
The protruding tip is the first answer I have seen that treats the port as a thing you can put away. When it is not needed the connector folds back into the body and the phone is a continuous object again, which is what a pocket wants. When it is needed it comes out, and the seal is on the tip rather than on a hole in the case.
The engineering is in the fold, and it is severe. A flexible joint carrying power and signal, on the outside of a device, in a pocket, in a tropical climate, has to survive moisture, dust and being sat on. That single part decides whether this is a design study or a product.
But the instinct is right, and it generalises. We accept holes in devices because we think of them as where things connect. A device that treats connection as an exceptional state — something the body does on occasion rather than permanently hosts — would be more durable, easier to seal, and oddly closer to the way we treat our own bodies.