Mobile devices are an essential element of our modern enterprises and lifestyles. According to Deloitte’s Connectivity and Mobile Trends report, mobile application consumption increased dramatically in 2020 compared to prior years in order for customers to better get access to products and services amid the COVID-19 epidemic. Their statistics also show that the majority of consumers’ heightened consumption is likely to remain long after the outbreak.

Smartphones, compared to bigger PCs or even laptops, provide consumers with rapid access to various products, and services. Mobile applications serve as a bridge between users and service providers. Given the intense competition in the mobile app sector, the value of a positive user experience cannot be understated.

Mobile application testing is critical to guaranteeing the success of your mobile application and providing a good end-user experience. This article will look at the difficulties that may emerge while undertaking mobile application performance testing, as well as the KPIs that are used to assess and analyze application functions.

Mobile Application Performance Testing Explained

The importance of testing in the creation of a mobile application cannot be overstated. Different tests, including functionality testing, usability testing, and performance testing, must be performed to discover flaws and bottlenecks for future application improvement. Specifically, t he performance of an application, is a decisive element in its success or failure. According to one report, application crashes during download account for 71% of customer rejections aka uninstalls. In such a competitive business, mobile app uninstalls and end-user dissatisfaction caused by bad app performance can impact the company’s image, and their reputation.

The software tester is focused on investigating the readiness of the mobile application as well as the influence of the application on the mobile device during performance testing. Mobile performance testing is carried out on both the server and client sides. Client-side performance testing includes examining how the application operates on the mobile device and the consequent performance as a result.

There are several types of mobile applications:

  • Web-Based Programs

    • Mobile web-based apps get data from the network and display it in the mobile browser.

    • Applications that do not require a platform to execute and instead rely on mobile browsers to obtain network data.

  • Native Applications

    • Applications that must be downloaded from an app store such as iTunes or Google Play

    • The software is installed directly on the device, and it is capable of storing data on the device.

    • Native apps need more hardware and system resources than web-based applications.

  • Hybrids

    • Hybrid apps may operate on both mobile web browsers and mobile devices via a platform.

Efficient mobile application performance testing necessitates evaluating the application across all application types to ensure performance, since each kind works differently with the server and the device.

Furthermore, depending on the device specs, apps demand varied use requirements. To guarantee a suitably high sample size for performance testing, testing must take into consideration mobile device user patterns.

KPIs for Mobile App Testing

In order to validate an application’s performance, the software tester must develop benchmarks that will be used to evaluate the software, also known as key performance indicators (KPIs). While a number of situations are evaluated during software testing mobile applications, the following important metrics are often used to evaluate and assess the application’s performance:

Response Time/Latency

Latency or response time is the time it takes between a consumer submitting a request and the system responding, measured in seconds. For example, if a user makes an in-app purchase and completes it, the response time is the time it takes from when the user first verifies their payment to when their request is submitted and validated, and a verification is sent to their account.

Response time increases when the number of simultaneous users exceeds a specific level, however depending on how bad this is, it may or may not be a concern you want to resolve.

One of the most important metrics to assess is reaction time, as a slower response time results in a terrible user experience, driving them to alternative products. Make sure your app’s response time does not exceed two to three seconds.

Load Speed

Load speed is the time it takes an application to completely start and load on the client user interface in seconds, and it should be recorded under the following criteria:

  • Expected Usage – Performance testing must mimic the actual conditions under which the application runs in real time. The load speed should be checked as a baseline for the estimated number of users or application requests.
  • Maximum Number of Simultaneous Users – The application’s load speed when the maximum number of concurrent users visit the application at the same time or when the maximum number of requests are reached. It is important to note that concurrent users are not accessing the same information at the same time, but rather separate aspects of the system.
  • Critical Situations – Load speed must also be monitored when the application is projected to receive a large number of concurrent requests. Critical condition testing is comparable to stress testing the application, in which the application is forced to its limits.

Make sure your website load speeds are as quick as possible to provide the optimal user experience.

Rendering on Screen

Screen rendering time, also known as page ready time, is the amount of time it takes for the software to load data into the interface and make it useable. This is a frontend metric that begins when a user’s browser first begins downloading information from a server and ends when all components on the webpage can be seen and they become responsive.

For instance, if you load a website with numerous high-resolution photographs, early content such as the banner, title, and text might load quickly. However, once you start navigating, the website may become “stuck,” with the page motion not following your hand motions as pictures, advertising, and videos load.

The time it takes for all items on the screen to be completely interactive is referred to as screen rendering.

Generally , the recommended time range for screen rendering is less than 3 seconds, based on the app’s size.


Throughput is the amount of requests that an application can tolerate without keeping them in a backlog. This is a fixed figure expressed in “transactions per second,” or TPS, and may be confirmed throughout performance testing.

If the number of requests goes beyond an application’s TPS, the end-user may have to wait for the application to answer. Throughput monitoring is important for identifying which components of an application cause bottlenecks.

Defect Rate

The defect rate can be calculated as the proportion of requests that resulted in failures compared to the total number of requests sent, or simply as the number of errors per second recorded.

The error rate is a critical indicator for assessing performance. While error debugging mechanisms can be employed to reduce the impact of specific problems, analyzing an application’s failure rates can reveal areas for improvement that impact the overall performance and, as a result, user experience and customer satisfaction. Admittedly, poor or insufficient performance might easily lead to app uninstallation.

App Crash

Another crucial KPI is the rate at which the program crashes per app load. Certain situations are likely to cause applications to crash. However, the frequency with which the program crashes might have a substantial impact on the user experience and result in uninstalling.

The user anticipates a minimum percent crash rate such as 1%.  To forecast the user experience and develop apps more, performance testing must track the app crash rate.

The KPIs we have listed are a selection of the most often used measures for assessing performance of a mobile application. More metrics can be collected and monitored to analyze certain areas of an application’s performance.