We live on a platform where users lead a world dominated by mobiles, where applications are expected to be fast, responsive, and easy to use. Research shows that users tend to uninstall apps quickly when they require slow loading times, resulting in app abandonment. Due to this reason, mobile app performance has become a crucial parameter for businesses looking to retain their users and avoid churn. Poor user experience and application store ratings can also be hindered by a slight delay when starting the application.

Meanwhile, the functionality of modern mobile apps is also increasing. Apps that provide 

  • High-end visuals, complex features and functionalities, offline capabilities, and third-party integrations tend to be large in size. 
  • This creates a clear trade-off between offering robust functionality and maintaining a lightweight app. 
  • Most larger apps find it hard to reduce app launch time and sometimes even use a bit of device resources without proper planning. This discrepancy is solved with effective optimisation of the app size.

Development can squeeze out Gbps of solid load time from the app just by optimising the assets, the code, the needed architecture, etc., without losing out on the essential features that you are building. This blog talks about the relationship between app size and performance and the best ways to balance the two.

Why App Size Affects Performance

Memory consumption and app launch speed

Larger apps have larger memory footprints due to asset, library, and resource loading at application startup. Also, when the footprint of an application is large, it can have longer start-up times when it is memory-intensive, especially on a device that has less RAM available. These types of delays can be perceived as users won’t be able to interact with the application as soon as they expect to.

Download time and storage impact on user adoption

Application size is a significant factor in how users choose to adopt mobile applications. The length of time it takes to download a large application can deter some users from doing so. This further emphasises the trade-off in mobile app speed vs. size, where most oversized applications have a high rate of abandonment during the installation process.

Background processing and battery usage

Due to the fact that larger applications consume a greater amount of system resources (i.e., CPU cycles) than smaller applications through additional background activity, larger applications are going to degrade over time and negatively impact the large app size overall system and user satisfaction.

Factors Contributing to Large App Size

Heavy images and videos

There are multiple reasons for the bigger application footprint and media assets like videos, animations, and images high in DPI add to it. Those also add to the application load time and take up space on a device in general.

Unused libraries or SDKs

Most apps have third-party SDKs that they partially use or not at all. Kotlin Multiplatform Libraries There are a lot of Kotlin libraries available, but when you ship the app, it will include all of these libraries whether they are used in any part of the code or not.

Large data files and offline storage

Offline features often require storing large datasets locally. While useful, excessive offline storage without proper management can inflate app size and negatively affect performance. Applying smart mobile app optimisation tips helps control this growth.

Methods for Reducing App Size with Minimal Loss of Performance

Compression of Images, Audio, and Video

One of the best methods to compress an app and reduce the overall size is through media compression. Media compression will allow you to achieve high-quality image/video/audio while at the same time reduce your file sizes by using current formats and optimal compression techniques. This method will provide you with an optimised app size and user experience.

Loading On-Demand Modules/Features

Loading on-demand modules/features will ensure that only the necessary features are loaded with the initial download of the app. When a user needs a specific module/functionality, those additional features/modules will be loaded. Loading on demand will improve app maintenance performance and keep the app running smoothly across multiple types of devices.

Removing Unused Libraries/Code

It will help you with the audit of your code and easy detection of unnecessary libraries, unused resources, outdated dependencies, etc. This enables you to get rid of these items from your app, reducing the amount of app ascent that ultimately renders at run time and thus ensuring a less tedious mountain of mobile app optimisation.

Using Vector Graphics Instead of Bitmap

Bitmaps take up more storage space than vector graphics. Since vector graphics are scalable, they are perfect for icons/UI elements. Using vector graphics will keep the app visually consistent while keeping the app size down.

Measuring the Effect of App Size on Performance

Use profiling tools (Xcode Instruments, Android Profiler).

Profiling tools are used by developers to analyze CPU usage, memory allocation, and startup behaviour. They get you the insights that you need to measure the app performance accurately and root out the unnecessary issues related to size.

Monitor app launch time and memory usage.

Tracking app launch time and memory consumption helps developers understand how size changes affect performance. A growing app size often leads to slower startup times and higher memory usage.

Track crash reports and battery consumption.

Large applications have higher chances of crashing your device or using excess battery. If you profile your application using a decent profiler for diagnostics, you can catch issues early to solve them before they impact users.

Examples & Case Study

One of the most well-known e-commerce apps was able to reduce their application size by nearly 35% by compressing their media files, eliminating unused SDKs and implementing modular functionality. This app optimisation case study had faster downloads and better reliability with increased user retention.

Another example of a social networking app was able to optimise their background process and asset usage, resulting in a substantial increase in mobile app performance. It also confirmed that application size affects performance, making the app start-up time for the app significantly lower.

Conclusion

The longer-term success for you will depend on you getting the right balance of space in your app without sacrificing too much performance. By​‍​‌‍​‍‌ regularly checking the metrics and applying best practices for optimisation of the app size, the developers can greatly improve app ​‍​‌‍​‍‌performance. Trying to reduce the size of your application by testing it continuously gives your users a smooth function.