How to Optimize Apps for Dual-Screen and Foldable Displays?

I thought the screen would feel new when I first tried out a foldable gadget. Something fun to do, but not something that would change the way you create things every day. I was mistaken. As soon as I opened the phone to a bigger screen, the app I was testing changed into a layout that seemed like it wasn't finished. Parts moved out of place. Buttons that looked good on a smaller screen were spaced out in an odd way. Suddenly, a clean design didn't feel right.

I sat in our Denver office holding this device and wondering how something as easy as opening a screen could show so many flaws. But that experience stuck with me because it made one thing clear: foldables do more than just change the layout. They change how people act.

Design has always been about behavior.

A Different Type of Canvas

Most smartphone apps were made to work on one fixed rectangle. You could turn it, but the real estate didn't move enough to change the content. Foldable and dual-screen smartphones brought something new: a screen that changes shape as the user moves.

When I talk to different mobile app development companies in Denver, I hear the same things over and over again. People desire tools that work well when the screen gets bigger, smaller, bends, or splits. They don't want the app to just stretch; they want it to move about in a way that takes into account the user's hands, vision, and work flow.

This isn't about following a trend.

It's about going to where people work.

Foldable phones are becoming more widespread in fields like fieldwork, logistics, medical outreach, and home services where teams need to be able to move about. The larger, unfurled display makes it easier for them to review information. When it's closed, the device fits back in your pocket. They get a portable device that doesn't take up any screen area.

As designers and builders, we need to see this as a natural feature of modern design, not something out of the ordinary.

Don't Worry About the Screen Size; Start With the Fold

I had to stop thinking of foldables as "regular phones with extra room" early on. That kind of thinking makes layouts stretch and spaces look strange. It doesn't mention the hinge, which is the most important part of the device.

The hinge makes everything different.

The user's grip changes when the device opens. The main point of concentration changes. Their thumbs hit different spots. They switch from using one hand to two hands without even thinking about it. This means that the design needs to take into account both the motion and the measurement.

In real life, this is what it looks like:

• Keep things simple when the gadget is closed.
• When it opens, give it a broader layout that makes it easy to see and sort.
• When the screen splits into two panes, think of each side as a small workstation.

People use foldables as a phone, a book, and a little tablet all in one device. The design has to support every state without making it feel like it has to.

Treat Dual Screens as a Conversation Between Two Spaces

Dual-screen gadgets add a unique feature: you can do two separate things at the same time. But the most important thing is not to give each screen the same amount of weight. The user doesn't often treat both panels the same. One space becomes the "main space," and the other becomes the "support space."

For instance:

• On the left, a document; on the right, notes.
• A map on one side and information about the destination on the other.
• One pane has a catalog, and the next has details on the items.

When I tried out early versions of split-screen capabilities, the mistake I kept seeing was a mirrored layout, where two screens showed the same content. That doesn't take use of the design at all.

It is best to think of the screens as companions. One person is in charge, and the other helps.

And when apps do this, the smartphone finally seems useful.

Features Come After Flow

You might want to think of foldables as a way to show more content. More buttons, text, and pictures. But having more screen area doesn't always mean you can accomplish more. It needs more control, if anything.

When the device gets bigger, people often change how they think. They look around longer. They read more slowly. They look around more. They look over the data. They look at their choices. They do things that need context.

This means that the app should:

• Spread out, not fill up
• Don't clog up free space
• Do not create shortcuts, but lower friction
• Slowly lead the user into the bigger layout

A screen that folds out isn't a billboard.

It's space to breathe.

Think in Terms of Transitions

The transition between states is one of the most important yet least spoken about components of foldable design. A smooth transition is more crucial than a precise plan. The interface should act like it knew the user was going to open a device from a small view to a broad view.

No cuts that jump.

No sudden changes.

No "Where did that button go?"

Good transitions make the user feel more stable. They're not only for looks; they also make things easier to think about.

When I worked with a logistics team in Denver, their main problem wasn't the layout. It was the time between states. When things moved too quickly, workers felt lost. The lesson was clear: the road, not the end point, defines a bendable experience.

Studying Real Hands, Not Ideal Layouts

Another thing that becomes extremely clear when you test foldables is that the thumb is not always the same. Things that function on a small screen don't feel good on a bigger screen.

Someone folded the device in half and put it on the table like a little tent during one of the tests. Someone else opened it all the way and held it like a book. Someone else put it down flat like a small tablet.

Three grips for the same instrument.

Placement is more important on foldables than on normal phones. Safe zones are not always the same. Touch points change. Suddenly, edges that were simple to reach are far away.

If you don't test real hands, you make things for fake ones.

How Foldables Fit into Daily Workflows

People transition between tasks in a way that makes foldables useful, not only because they look cool.

People who work in the team of mobile app development in Denver typically talk about people who are on the move, such technicians, field inspectors, delivery teams, medical staff, and on-site managers. These people don't sit at desks. They execute digital jobs while also handling tools, equipment, and papers.

A device that fits in a pocket and is big enough to hold in one hand is better for their work than any flat phone.

Apps that work well on foldables help them:

• see diagrams more clearly
• compare two things without going to a different tab
• Fill out forms with fewer breaks
• watch data on two panels

It's not a luxury. It's comfort.

It's not a trend. It's useful.

Looking Ahead

Foldables won't take over everything, but they will become more important each year. Not because they're new, but because they work in real life and fix real problems. It's not hard to learn how to design for them; the hard part is learning to see them as normal.

As designers and builders, our role is easy: keep asking questions about how people use their devices, do their activities, and adjust to the changing shape of their screens.

When you optimize for foldables, you don't have to make big changes to the layout or use visual trickery. It's about realizing that the screen is no longer a set canvas. It breathes. It can bend. It changes.

And our plans need to change with it.