The hard problem in a foldable phone is not making a screen that bends once. It is making one that bends thousands of times without cracking, lifting or collecting dust. Most of what separates a good foldable from a fragile one comes down to the display layers, the hinge and how well the two are sealed.
Two shapes
Foldables come in two forms. A book-style foldable opens sideways like a small book, turning a phone into a tablet-sized screen. A flip-style device folds a tall phone in half to a compact square. Most have a smaller screen on the outside so the phone remains usable while closed.
What the screen is made of
The inner display is built from very thin layers on a flexible base. Manufacturers describe combining a thin, flexible glass layer with protective polymer films, trading a little scratch resistance for the ability to bend. The panel technology is usually OLED, where each pixel emits its own light, because it adapts well to thin, flexible layers. Our comparison of OLED and mini-LED displays explains how it differs from other screen types.
The practical consequence is that a foldable’s inner screen is softer than the glass on a regular phone. Fingernails, keys and grit can mark it, which is why many models ship with a protective film already fitted that is meant to stay in place until a service center replaces it.
Hinges and dust
Hinge design has become a headline feature. Google says the gears in its earlier hinge design left small gaps where dust could work its way in, and that it removed them in the Pixel 10 Pro Fold with a gearless hinge, and Google says the phone is rated IP68, which it describes as a first for a foldable. Samsung’s Galaxy Z Fold7 uses a different approach, an Armor FlexHinge with a multi-rail structure that Samsung says spreads stress more evenly and reduces the visibility of the crease.
The ratings deserve a careful reading. IP codes come from an international standard, IEC 60529. The first digit describes protection against solid particles and the second against water. Samsung lists the Fold7 at IP48, and its footnote explains that the 4 means protection against solid particles larger than 1 millimeter. That is not dustproof, and Samsung says so in its own support material. Google’s IP68 claim is stronger on dust, but its footnote notes the phone is designed to meet the rating when it leaves the factory, that it is not waterproof or dustproof, and that resistance can decline over time with wear, repairs or damage.
In short, newer foldables are better sealed on paper than early ones, but sand, grit and pool water remain a risk, and the ratings are laboratory conditions.
The crease
Every foldable shows a faint line where it bends. Makers say newer hinges reduce it by letting the display curve gently instead of folding sharply, and Samsung describes a significant reduction in how visible it is. None claims to have eliminated it. How much it matters is personal: some owners stop noticing within days, while others find it distracting when reading or watching video.
Questions worth asking before buying
- Which shape fits how you use a phone? A book-style device suits reading and multitasking. A flip suits people who want a small phone that opens up.
- What do the dust and water ratings say, and what do they not? Read the footnotes, not just the code.
- What does the warranty cover? Screen damage is the most expensive failure, so check whether it is included and what a replacement costs.
- How do your most-used apps behave on a larger or changing screen? Try them in a shop if possible.
- How does it feel in the hand? Foldables are usually thicker and heavier than slab phones, and thin bodies leave less room for the battery, a trade-off explained in our guide to battery health.
For people who read, work on documents or run two apps side by side, the extra screen can justify the cost and complexity. For people who mostly message, browse and take photos, a conventional phone is cheaper and sturdier.
