Gemma Lara Savill
App optimization strategies. Make your app faster, cheaper and offer a great user experience
By Gemma Lara Savill
Published at April 20, 2024
Have you ever noticed your app slowing down as you add more features? This is a common issue, and often the culprit is inefficient data transfer and API calls. Fortunately, there are well-established strategies to optimize your app for speed and data usage.
Here's how to identify optimization opportunities and apply the right strategy:
Analyze Network Traffic
Look at the data being fetched and the frequency of those requests. Focus on:
- API Calls: How many are being made and are they necessary for every screen refresh?
- Data Size: Is more data being used than needed for the current task?
The Power of Caching
Caching stores frequently accessed data on the user's device, dramatically improving performance and reducing network usage. Let's see how:
- Cache Immutable Data: Information that doesn't change, like a dog breed in a pet app, can be cached locally, eliminating unnecessary server calls.
- Cache for Defined Periods: Data that updates periodically, like a movie list refreshed every two weeks, can be cached for that duration. When the cache expires, fetch fresh data.
Here's a key point to remember: you should implement mechanisms to invalidate or refresh the cache to ensure it reflects updates on the server. This mitigates the risk of data divergence between the cache and the server.
Beyond Caching
- Leverage Pull-to-Refresh: The pull-to-refresh gesture, a common pattern in mobile apps, can be used for more than just refreshing the UI. It can also be a trigger to refresh your local data cache. This gives users control over when they want to check for potentially newer data on the server, even if the locally cached version might still be valid.
- Optimize Data Transfer: Instead of fetching entire objects, you can focus on requesting only the specific data needed for the current view.
- Pagination: For large datasets, implement pagination to load data in smaller chunks, reducing initial download times. In this example from my PopularMovies2.0 repository, the app demonstrates proactive network calls. As the user scrolls, data is fetched in advance and cached locally. This prioritizes the user experience by making local data the source of truth of pagination, resulting in faster loading times.
Here you can see the example in action: smooth infinite scrolling as we anticipate getting the pages from the server into the local cache (no waiting around for Movies to load).
Prioritize User Experience
While data fetching is crucial, avoid skeleton screens that leave users staring at a blank canvas until all APIs respond. Here's a better approach:
- Progressive UI Rendering: Get users interacting faster by displaying the core UI layout instantly. Leverage cached data to populate initial content.
- Load Data Incrementally: As API responses arrive, progressively fill in the remaining UI sections. This keeps users engaged and informed about the loading progress.
Benefits of Optimization
By implementing these patterns, you achieve multiple benefits:
- Enhanced User Delight: Faster loading times, a responsive app, and immediate content availability contribute to a more enjoyable user experience.
- Improved Performance: Faster loading times and a smoother user experience.
- Reduced Data Usage: Lower costs for both you and your users, especially on limited data plans.
- Offline Functionality: Cached data allows users to access some features even when offline or when the server is down.
Conclusion
Optimizing data transfer and API calls is an ongoing process. By analyzing network traffic, implementing smart caching strategies, and prioritizing a progressive UI experience, you can create a faster, more cost-effective, and user-friendly app.
