Crash Rate


What is crash rate?

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Team Storyly
May 22, 2023
0 min read

What is crash rate?

Crash rate refers to the percentage of times a particular application or system crashes or fails to function properly during a given period of time. It is usually measured as the number of crashes divided by the total number of sessions or operations performed. A high crash rate indicates that the application or system is unreliable and needs improvement. Measuring and monitoring crash rate is important for ensuring the stability and performance of software applications and systems.

How is application crash rate calculated?

You can calculate the crash rate by dividing the number of times a user has launched the app by the number of crashes occurring within the same time period. You can then multiply this number by 100 to give you a percentage. Typically, this accounts for a 24-hour period, which is normally sufficient for gauging the performance of an app on a daily basis and identifying specific issues.

For example, an app might see 21 opens and 3 crashes in a day. This would give you a 14% crash rate, which is much higher than what you would want. Generally, the ideal app crash rate is less than 1% per user, less than 0.1% per session, and less than 0.01% per screen view.

Before launching any app, it's important to minimize the app crash rate and ensure good performance. Regardless of the quality of the rest of the user experience, a high crash rate could mean the difference between a successful and failed app.

The visual displays the formula for "Crash Rate". It is found by dividing the number of times an app is launched by the number of crashes and multiplying the result with 100. There is a Storyly Glossary logo at the bottom right.
Calculation of crash rate

What causes an app to crash?

There are several reasons why an app might crash. So, what does a crashing app mean, exactly? The following are some of the main issues that can lead to a high crash rate.

Inadequate testing

You should always test your app before launching it and continue testing it to ensure it continues to function properly. Even if you test it frequently, you need to ensure you're correctly testing it and that your tests aren't superficial. 

Testing normally involves running the app in various environments. For example, you might try to run the app on Androids, which could indicate your Android app crash rate as compared to your iOS crash rate. You can also test the app with different specifications to see if these interfere with the user experience and contribute to app crashes.

Incompatibility with specific devices

Another potential cause of app crashes is incompatibility with certain devices. Keep in mind that this is likely to be a bigger issue with Androids than Apple devices. While Apple has complete control over the iOS app environment, this isn't the case with Android. There isn't as much uniformity with Android, which is due to a number of factors. One of these factors is the versatility of hardware, with components sourced from different manufacturers. In addition, you'll have to contend with different iterations of Android operating systems. 

If you need assistance with this, Android offers a support library with plenty of resources.

Poor memory management

Memory management is among the biggest challenges that app owners face. Often, poor memory management could cause apps to crash by consuming too much of the device's memory. In other cases, the user may simply have too many apps open, limiting the amount of space needed for the app to run.

When developing an app, it's important to remember that users will likely have several other apps open at the same time. As such, your app should be able to accommodate these neighboring apps and provide a consistently smooth experience. This is where iOS development can be more advantageous than Android.

On Android devices, developers have more control over memory, but this can present certain difficulties. These issues frequently arise from bitmap processing or large image file sizes, which often cause memory shortages in Java. However, iOS isn't without its own memory issues, as developers could inadvertently cause an NSInternalInconsistencyException when modifying a data collection or array in a single location at the wrong time.

Network errors

Network issues may also cause apps to crash. They may occur when your app attempts to access data via third-party services or a network. When the network experiences instability, the app may simply shut down due to the delayed response.

Another potential reason for network errors could be loss of reception depending on the user's location, or the change from wi-fi networks to 3G, 4G, or 5G. 

One effective solution for this is to provide users with an offline version of your app, if possible. If this isn't doable, you may be able to simply display the most recently loaded app version to prevent the app from crashing altogether.

Poor optimization on the front end

Apps may crash due to issues with the front end of the app, even though most issues stem from poor back-end optimization. One of the biggest culprits in this regard is poor media optimization. This could involve bulky images, videos, and other media files that tend to overload the app. 

You can use certain optimization tools to prevent front-end problems from bogging down the app experience and potentially causing crashes. In addition to media optimization, you'll want to avoid using certain inline styles such as needless child elements.

Over-abundance of code

Of course, too much code could be the cause of app crashes, making it important to simplify your app as much as possible. Some developers may get too carried away with the code they use. However, this can easily contribute to crashes. Instead, only use the code that you need to ensure the app performs properly. 

In addition, take the necessary steps to weed out various bugs and continually optimize the app over time. This will further reduce crash instances.

Software lifecycle disruptions

As an app advances, it will likely see new releases that make the app even more appealing to new users. At the same time, issues may arise due to the loss of the conventional software lifecycle. 

The disruption of the software lifecycle could cause crashes in several ways. For instance, users may fail to download the new version of the app as required. Other instances could include unstable or updated operating systems that are no longer compatible with the current app version. 

The software development life cycle typically involves multiple phases: planning, analysis, design, implementation, testing, and maintenance. Properly managing the app over the course of this lifecycle can prevent potential problems from developing.

Poor error and exception handling 

Your app is bound to experience various errors throughout its lifetime, but you must be able to properly handle and mitigate them. You should have steps in place to correct a multitude of possible errors. You'll need to anticipate everything from memory and network issues to sudden API changes that might otherwise compromise the app.

Good coding will help you avoid crashes resulting from the many inevitable errors your app is likely to encounter. This will also notify users of errors within the app, which will at least provide an explanation for them in the event of an issue.


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