How do you make your app look good on different screen sizes, orientations and font sizes?

What the interviewer wants to hear

• Use flexible layouts instead of fixed sizes
• Use density-independent units and scalable text (sp, Dynamic Type)
• Adapt layouts using window size classes or breakpoints for tablets and foldables
• Respect safe areas, notches and system bars
• Test on small, large and rotated screens with large fonts

Model answer

I start with flexible layouts: rows, columns and constraints that fill available space instead of fixed pixel widths. Sizes use dp or points, and text uses sp on Android and Dynamic Type on iOS so it scales with the user font setting, which means layouts must allow text to wrap. For tablets and foldables I use window size classes or breakpoints to switch layouts, for example a list and detail side by side on wide screens. I respect safe areas and insets so content is not hidden behind the notch, home indicator or keyboard. Then I test on a small phone, a large phone, a tablet and landscape, plus the largest font size, using previews in Compose or SwiftUI and real devices for the final check.

More easy Mobile App Developer questions

• What is the difference between native and cross-platform mobile development? When would you choose each?
• Explain the lifecycle of a mobile app screen. Why does it matter?
• How do you handle network calls and errors in a mobile app?
• What is MVVM and why is it used in mobile apps?
• How do push notifications work in a mobile app?
• How do you run slow work like network calls or database reads in a mobile app without freezing the UI?
• What options do you have for storing data on the device, and how do you choose between them?
• How do you request runtime permissions like camera or location, and what do you do when the user says no?
• What is the difference between declarative UI (Compose, SwiftUI, Flutter, React Native) and the older imperative style?