The number of smartphone users is growing day by day. Along with this, we can see an increase in the number of mobile applications. It is not surprising as modern applications can solve literally any problem. Today, they are even actively used in the healthcare and military spheres. However, along with the growing popularity of mobile applications, we can also notice more demanding requirements for them. So in order not to lose potential clients and users, it is crucial to consider all aspects of mobile app quality. In these terms, performance issues are of primary importance. It is just impossible to launch a mobile application without prior comprehensive performance testing. So, let’s consider the main aspects of software performance testing and the way it should be executed for mobile apps.
What is performance testing?
Even if you are just a newbie, you probably know that software performance testing is a non-functional type of software testing carried out to check whether an application works smoothly while being subjected to various workloads. A workload is a certain number of synchronous transactions or users. During performance testing, such app characteristics as speed, scalability, stability, and reliability are verified.
Based on the level and nature of workload several types of software performance testing are differentiated:
Stress testing — app behavior is tested as it undergoes extreme workload going beyond the estimated limit.
Volume testing — app behavior is tested as its DB is filled with a great amount of data.
Load testing — app behavior is tested as a workload is gradually growing but does not go beyond the estimated limit.
Spike testing — app behavior is tested as a workload rapidly rises up for a short while and equally rapidly drops down.
Stability testing — app behavior is tested as it is subjected to a normal level of workload for a long time.
Scalability testing — app testing for an ability to scale up or down in response to an increase or decrease in the number of concurrent users.
Performance testing is not carried out manually, and special tools are leveraged for load simulation and performance parameters measurement.
Importance of performance testing
Software Performance testing plays a special part in the scope of mobile app testing. The thing is that the performance characteristics significantly affect user experience and have an influence on business success.
An application with even the most advanced and valuable features and state-of-the-art UI/UX design does not have a chance to take off in case it has poor performance. Today’s users do not tolerate a long response time, numerous crashes, errors, memory leaks, high battery consumption, and other inconveniences. Consequently, if you are serious about your business and eager to acquire a great deal of new users and retain them, performance testing is not a thing to be neglected. On the contrary, it always makes sense to ensure great app performance during usual workloads and in high seasons when your app can be subjected to traffic spikes.
Peculiarities of mobile performance testing
It is obvious that mobile applications differ from web applications, so there are certain differences in the execution of performance testing as well. Below we are going to represent the main factors having an influence on mobile app performance testing that consequently should be taken into account:
Your target audience can leverage mobile devices of various types, different brands, and with diverse hardware and software configurations. Consequently, an app can have different performance characteristics defined by the used device. Therefore, varied mobile devices should be taken into consideration while executing software performance testing, and the following metrics must be checked:
This is undoubtedly the first performance parameter evaluated by end-users. It is deemed to be a golden rule, that a splash screen of an app should be displayed within 1-2 seconds after tapping on an app icon.
App retrieval after being in the background
Whenever an app is retrieved after being run in the background, it should be in the same state as it was before, Otherwise, data gets lost, and a user has to fill in the data again from scratch.
Before the app launch, it is of primary importance to check how the app consumes memory. The thing is that certain functionality of mobile applications may cause high memory consumption. For instance, the implementation of push notifications in Android apps always leads to an increase in memory consumption. Factors like this must be properly handled in order to avoid users’ disappointment.
While being continuously used mobile applications may extremely drain a battery and heat a device. This incredibly impacts the performance of any application, and it usually happens when the app uses more resources than required.
Performance can be considerably degraded by high CPU consumption. So it is strongly advised to monitor the CPU consumption by an app during spikes and long-term excessive usage.
When an API is used for an app interaction with a server, the following aspects influencing performance should be checked:
Data submitted to and from a server
Data submitted by a server must be appropriately handled by an application and its loading should not take an eternity. Even if the data is submitted in a particular format that must be converted to a relevant one, it should be done within an appropriate time frame.
The number of generated API calls
More than often numerous API calls for the same functionality can be generated by an app. This inevitably affects app performance. To improve performance, it is recommended to decrease the number of calls.
In case a server is down for some reason, the data must be saved in a native database. Another option is failover/backup servers that must be in ongoing synchronization with a major server. In such a way, it is important to check that plan B is available and users can get data even if the server is unreachable.
Apart from diverse devices, your users can also use various networks, and an app may perform in a different way on different networks due to the fact that network protocols can cause delays and throughput. To mitigate related risks, the application must be tested on different mobile and WI-FI networks with different speeds. Additionally, it is worth inspecting app performance while switching from one network to another. Latency and jitters are often caused during network switching.
Strategy for mobile app performance testing
To get the most out of testing it is advised to start with a test strategy design. While it can vary the usual performance testing plan suggests such steps as: Identification of requirements for testing environment
Define which hardware, software, network configurations, geolocations, and tools should be utilized to set up a testing environment maximally mimicking a production environment. Only a test environment that properly copies the real one can provide testers with accurate testing outcomes.
Identification of required performance metrics
Identify business needs and on this ground define performance tests that should be carried out and testing metrics that should be gathered. Response time, throughput, the maximum number of concurrent users, CPU utilization, memory utilization, battery utilization, error rate, etc. are common software performance testing metrics.
Determination of acceptance criteria
Acceptance criteria are used as benchmarks letting a team understand whether tests are passed or failed. As a rule acceptance criteria are defined on the ground of business needs and industry standards.
Test scenario selection
To design tests that will provide adequate outcomes, it is vital to leverage use scenarios that are of critical importance for business. To get this information it is necessary to cooperate with business analytics and analyze real user behavior.
Test design and development
As soon as appropriate test scenarios are defined, performance tests are designed and scripted with consideration of user roles, test data, and required testing metrics.
Test execution goes next. At this phase not only tests are run but also corresponding data is gathered.
Reporting, well-tuning, and retesting
Test outcomes are compared with acceptance criteria and a comprehensive report is generated. If there is a need to eliminate certain performance-related issues and bottlenecks, an application under test is well-tuned and tested again.
Top mobile performance testing tools
To succeed with software performance testing it is important to choose appropriate tools. Below you can find the most helpful mobile performance testing solutions:
Neoload is a unique cloud-based tool enabling the creation of realistic performance tests. It supports different real devices and emulators, along with the latest versions of operating systems. What is important, Neoload lets QA teams fulfill real-life scenarios including network issues, varied devices, and multiple geolocations.
This well-known open-source tool is suitable for testing either web or mobile apps. It is incredibly user-friendly and has a wide spectrum of features including numerous load generators and controllers.
This is one more cloud-based tool enabling accurate mobile app testing by harnessing the power of AI and ML. With its help, complex performance and load testing are painless.
Apptim is a useful performance testing solution. It is suitable for iOS and Android applications. With its help, QA engineers can measure resource utilization and plenty of other parameters.
With this open-source performance testing tool, it is indeed easy to carry out efficient load testing and measure diverse performance characteristics.
Performance testing plays an important role. Performance characteristics substantially determine the success of a mobile application. Only a fast, robust, and scalable application can win users’ hearts. So, it is worth spending time and effort on performance testing. Still, to get accurate test results it is essential to set up a realistic test environment, check different geolocations, choose the right testing tools, pick up appropriate test scenarios, etc. Moreover, as long as mobile applications considerably differ from web applications, QA teams also should consider such factors as utilization of device resources and various types of network connection.
In the course of performance testing, important metrics are gathered and assessed. It uncovers critical bottlenecks that should be fixed before a mobile application is delivered to end-users. So, it is a golden rule to have a comprehensive approach to mobile app performance testing.