4 Essential PWA Strategies for Enhanced iOS Performance

Progressive web apps (PWAs) are a clever solution that balances developer resources and consumer expectations. Instead of spending countless hours developing a native app, businesses can build a PWA that operates in the web browser, giving users the quality experience they expect without expending all of the company’s resources.

PWAs deliver app-like experiences, including offline functionality and push notifications, giving companies and consumers the best of native apps in a different environment. PWAs are a win-win solution, but when it comes to iOS devices, developers have to optimize PWAs for performance.

In this guide, we’ll share a range of essential PWA strategies and help you maximize their potential on iOS devices.

In this article:

• Understand iOS Limitations for PWAs
• Optimize Service Workers
• Enhance the User Interface
• Test and Debug on iOS
• Bridging the Gap Between iOS Requirements and PWAs
• Frequently Asked Questions

Understand iOS Limitations for PWAs

PWAs offer so many benefits, but due to the unique constraints Apple places on developers, optimizing them for iOS is crucial. Unlike other platforms, iOS limits certain PWA features, so developers have to get creative.

For example, one relatively recent change occurred in February 2024, when Apple announced it had removed home screen web apps (PWAs) for iOS users in the EU. This was to comply with the EU’s Digital Markets Act (DMA), which would require home screen web apps built on alternative web browsers.

This capability, in Apple’s view, was a security risk, as it could allow malicious apps to gain access to user’s devices.

Beyond this, developers can only build effective PWAs when they understand iOS limitations on:

• Service workers: iOS has strict rules on background processing, so service workers can’t do as much. They can still cache content and work offline, but they can’t perform other tasks in the background as well as they do for Android users.
• Push notifications: iOS PWAs automatically opt users out of these notifications, making it more difficult for brands to build a subscriber list.
• The home screen experience: Users can add PWAs to their home screens on iOS, but it isn’t as seamless as on other platforms. When launched from the iOS home screen, PWAs lack native-like features, which negatively affects engagement.

Unfortunately, iOS limitations lead to reduced offline functionality, lower user engagement, and an inconsistent user experience between iOS and other platforms. Instead of seeing this as a loss, developers should understand these limitations and work within them to find better ways to serve their user base.

Optimize Service Workers

Service workers allow PWAs to work in the background and send push notifications, but if you’re working with iOS, you’ll need to optimize these service workers to operate as efficiently as possible within Apple’s constraints.

Improve your service workers with:

• Caching: Tell the system to prioritize caching critical resources, like certain assets and content, for core functionality. It’s also good to set up cache expiration policies so cached resources regularly update.
• Background syncing: Optimize background syncing by batching multiple sync tasks to minimize battery drain. You can also set up throttling to control the frequency of background syncing.
• Optimizing push notifications: Optimizing notification payloads improves speed and performance. iOS doesn’t allow for as much multimedia content as other platforms, so focus your energy on the meat of the content instead of visuals.

Enhance the User Interface

Quality UI is always a best practice, but you also have to play nicely with Apple’s Human Interface Guidelines (HIG). This requires consistency with your web app’s layout, typography, and visual design. Responsive design is also a best practice, allowing the PWA to adjust to different screen sizes and rotations seamlessly.

Create a UI that feels native to iOS by:

• Using iOS-style navigation bars and tab bars to organize content and facilitate navigation within the PWA.
• Setting up modal dialogs and alerts using iOS-style components to provide contextual information and prompt user actions.
• Supporting Dynamic Type to ensure that text within the PWA adjusts to the user's preferred font size settings.

Test and Debug on iOS

Testing solely on Android devices will set you up for failure. Always test iOS experiences on Apple devices to get an accurate view of the true iOS experience. We recommend using tools like:

• Safari Developer Tools: Safari's built-in developer tools, including the Elements, Console, Network, and Application tabs, provide a comprehensive set of features for testing and debugging PWAs.
• Console Logging: Strategically place console.log statements throughout the PWA codebase to log relevant information and debug errors.
• Emulator Testing: While testing on physical iOS devices is crucial, developers can also use emulator tools like webpushtest.com to replicate iOS environments and test PWAs on virtual devices.

Bridging the Gap Between iOS Requirements and PWAs

There’s a lot to love about progressive web apps, but iOS requirements? Not so much.

Developers should understand iOS limitations for PWAs and work within that framework to develop effective, creative solutions to limited user engagement. You can’t change Apple’s guidelines, but you can optimize your PWA to operate at its best under these constraints.

Notifications are a must for any PWA, but setting them up isn’t always easy. When you need engagement ASAP, set up an all-in-one inbox that allows you to communicate with users across platforms.

Sign up for MagicBell now to see how our real-time notification inbox supports simpler in-app and push notifications for PWAs.

Frequently Asked Questions

Are PWAs compatible with older iOS devices?

Yes, PWAs are compatible with many devices and operating systems, including older iOS devices, and developers should still consider performance optimizations and fallback mechanisms to ensure a smooth experience on devices with older iOS versions.

Can PWAs access native device features on iOS, such as the camera or GPS?

While PWAs on iOS have limited access to device features compared to native apps, certain capabilities are available through web APIs. For example, PWAs can use the device's camera, geolocation, and other sensors using APIs like the MediaDevices and Geolocation APIs.

However, developers should still be aware of the restrictions and limitations imposed by iOS when setting up these features.

Do PWAs on iOS support background synchronization and offline functionality?

PWAs on iOS support background synchronization and offline functionality to a certain extent. While iOS imposes restrictions on background processing, service workers can still cache content and resources for offline access.

Developers can optimize service worker performance and implement strategies, such as background sync and caching, to improve offline capabilities on iOS devices.