What Foldable Phone Cases Protect, and What They Leave Exposed

Cases for foldables are built differently from cases for standard phones because the device bends at a hinge. They typically come in two parts. One covers the back and sides, including the charging port and the camera island, with a slightly raised edge intended to keep the camera lenses away from direct impact. The other covers the front and the screen through a raised lip around the perimeter.

The coverage stops there. These products are closer to covers than to full enclosures, so they do not offer 360-degree protection and they do not protect the hinge. Samsung's Carbon Standing Case for the Galaxy Z Fold 8 emphasizes an anti-reflective film and a built-in kickstand, which Engadget describes as convenience first and protection second. Casetify's upcoming iPhone Duo case claims technology that disperses energy from drops and a specialized Duo-Lock hinge protection; the company already sells a Galaxy Z Fold 8 case line with similar hinge protection, which adds heft as a trade-off. Some basic cases leave the cover screen unprotected as well, and buyers can add a separately purchased screen protector or a kit for the outer display.

Rugged models from brands including CaseBorne, Supcase and Otterbox add hinge protection, connecting the front and back in one piece and offering all-around coverage with a screen protector included. The Supcase Unicorn Beetle Pro case for the Galaxy Z Fold 6, for example, has a built-in tempered glass screen protector and hinge protection that doubles as an S Pen holder, but it is bulky.

Dust remains the harder problem. When a foldable is closed at the hinge, dust sitting on the screen can be caught in the hinge mechanism in much the same way as on a laptop, and even microscopic particles that are invisible to the eye can damage the screen or crack it. That is why many foldables carry lower dust-resistance ratings than traditional bar phones, though the situation is starting to change.

The iPhone Duo and Google Pixel 11 Pro Fold carry an IP68 rating, higher than older foldables. The Samsung Galaxy Z Fold 8 meets only an IP48 rating, which means fine dust particles can damage the screen and hinge, and the Motorola razr fold meets an IP49 rating that denotes the same level of solid-particle protection; the first number in the rating indicates the protection against solid foreign objects 1mm in size or larger. No foldable phone case on the market prevents dust from being trapped in the folded screen or in the hinge.

Engadget's advice is to both use a case and wipe the phone down before closing it every time, and to use a soft brush periodically to clear dust from the outside of the hinge. That requires more care than a traditional smartphone, but keeping dust out matters even with a sturdy case and a more durable foldable.