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Large List Rendering: Infinite Scrolling in Mobile Apps

Large List Rendering: Infinite Scrolling in Mobile Apps

Learn how to design smooth, resource-efficient infinite scrolling experiences for mobile apps.

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Modern mobile users expect seamless, responsive interactions, especially when browsing dynamic, content-heavy feeds like Instagram, Twitter, or an e-commerce app. Behind-the-scenes, these smooth scrolls across potentially endless data are powered by a design pattern known as infinite scrolling.

But delivering infinite content on mobile isn’t free. Devices have limited memory, network variability, and tight performance budgets, especially when juggling animations, images, and user gestures. If done wrong, infinite scrolling leads to sluggish UIs, janky scrolls, and frustrated users.

This lesson will help us understand how to architect and implement infinite scrolling within mobile system constraints. We’ll explore its core principles, common pitfalls, life-cycle aware design, and platform-specific implementation strategies.

Let’s start by understanding large list rendering.

Large list rendering

Large list rendering in mobile apps refers to the challenge of efficiently displaying and managing extensive datasets, such as social feeds, product catalogs, or chat histories, without compromising performance or draining resources. When not designed carefully, rendering long or dynamic lists can lead to:

  • Sluggish scroll performance

  • High memory usage

  • Increased battery drain

  • Crashes on low-end devices

These effects can severely degrade the user experience, especially on mobile, where hardware constraints and user expectations are stricter than on the web. To tackle these challenges, mobile developers rely on patterns like pagination and infinite scrolling, which allow content to be loaded dynamically as needed instead of all at once.

We’ll begin by exploring pagination, a foundational pattern in mobile data loading that still powers many infinite scrolling implementations under the hood.

Pagination in mobile apps

Pagination is a classic data-loading strategy where content is divided into discrete “pages”, each containing a fixed number of items, and fetched as needed. While it’s often associated with page numbers on the web, its role in mobile is more structural than visual.

In mobile System Design, pagination is frequently used behind-the-scenes to manage memory, bandwidth, and network performance while keeping the UI responsive.

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An overview of pagination in mobile apps
An overview of pagination in mobile apps

Let’s look at three commonly used strategies.

  • Page-based pagination: This divides content into fixed pages, e.g., 20 items per page, and loads a specific page when requested. It’s easy to implement and works well when the dataset doesn’t change frequently. In the example below, the fetchPage function retrieves a specific set of products from the server based on the given pageNumber and renders them on the UI.

function fetchPage(pageNumber) {
    fetch(`/api/products?page=${pageNumber}`)
    .then(response => response.json())
    .then(data => renderProducts(data));
}
Example code snippet to depict the use of page-based pagination

Limitation: It is prone to duplication or missing items if new data is added/removed during navigation.

  • Cursor-based pagination: Instead of page numbers, the server returns a cursor (e.g., the ID of the last item), which the ...