The rapid transformation of mobile devices from being simple handheld computing devices, to highly sophisticated, complex and multi-function tools over the past two decades, has been phenomenal. Mobile devices with increased functionalities are widely available and can be more economical than a PC or laptop, although often more powerful. Because so much business is being done on tablets, Smartphones, and wearables these days, there is concern about the reliability of mobile applications because of the important tasks being regularly performed on handheld devices. Mobile application testing is essential for attaining data about usability and to make sure that security is maintained. The user demands access to the application whenever they choose to use it, and expect exceptional response times regardless of network or device.
Mobile Applications Testing and its Significance
There exist three kinds of mobile applications:
Native Applications: For use specifically on mobile devices.
Mobile Web Applications: These are web applications modified so users can view them on the respective browser installed in their mobile device.
Hybrid Applications: These are a combination of native and mobile web applications and are installed on the application as they were a native app but are actually a web app.
Mobile application testing can be a challenging process, when compared to web application testing. The dynamics of this type of testing is different because it is a time-consuming and complex process, but still has to guarantee the consumer’s satisfaction. Few of the main challenging factors are as follows:
- Test over a wide range of devices with various screen sizes, hardware components, software features, and OSs.
- Test on different manufacturers in the market such as Apple, Samsung, Huawei, HTC, Nokia, etc.
- Assess multiple operating systems and versions such as iOS 12.2, Oreo 8.1, etc.
- Frequent updates make some features or piece of code outdated so a new iteration of testing with modifications will be required.
There may be millions of users for a certain application and it will be disastrous if a bug is found, which can result in irreparable damage to the brand reputation as well as big monetary losses.
Types of Testing for Mobile Applications
Similar to web application testing, mobile applications have quality characteristics (functional and non-functional) which need to be tested.
1. Functional Testing
This type of testing is executed to assess the functionality of the application. In mobile testing, functional testing will be divided into the following:
- Correctness: Test the suitability and accuracy of the application. If the functionality is working as expected and according to the specification, then it is correct, and if the data is displaying correctly then it is recorded as accurate. For example, if an application is unable to scale an image to fit on the screen then it is not suitable, and if scaling down the image is working as expected but the image is wrong then it is inaccurate.
- Security: Vulnerabilities need to be identified because mobile applications are usually more prone to hacking and security breaches. Security testing is best executed by security experts, but testers should have the basic knowledge to uncover security loopholes in the application. There are tools available on the market, but it is still preferable to have a good understanding about security along with the technical ability for scripting the test cases.
- Interoperability: This refers to testing that makes sure that all the integrated components of the application interact with each other and with other systems as they should, without any problem. For example, if a user captures an image from the camera then they will expect to be able to share through different applications such as Facebook, Email, or Whatsapp.
2. Non-Functional Testing
Non-functional testing is performed to assess the preparedness of the application. In mobile testing, non-functional testing will be divided into the following:
- Performance Testing: This refers to the response time of the application at a given load condition. The interaction of the application with the server should work efficiently, otherwise if the performance is poor the user will likely abandon the application. Many tools are available in the market to evaluate an application’s performance but good knowledge is required to be able to operate such tools.
- Usability Testing: Compared to web applications, mobile applications have a greater user base across the world because mobile applications are accessible anywhere and at anytime. If the application has good functional features but poor usability then abandonment of that particular application by the user is significantly higher. Along with checking colors, and accessibility, mobile applications must be check for the following:
- Simplicity: They should be simple and provide ease of use
- Intuitiveness: The user’s expectation is that the mobile application should load immediately after it has been installed on a device. From there, the user will play with the application for some time to determine the ease of use. If it is difficult and not intuitive, then there is a high chance user will uninstall and look for different application.
- Navigate: Navigation in the mobile application should be simple and direct, and not pass through convoluted options which the user will not like.
- Reliability Testing: With mobile applications being everywhere and populations becoming more dependent on them, reliability has become a mobile application’s core quality determiner. Reliability testing is performed to assess how gracefully mobile applications recover from unexpected situations, how well they handle any faults, and to check consistency in providing the same result for the same particular actions.
Other than these headings, testers should keep in mind following generic categories while testing mobile applications:
- Mobile applications need to be accessible on demand.
- Every device has different capabilities and features, such as operating systems, displays, and battery consumption. Therefore mobile application testing should be diversified among various devices.
- Mobile applications are developed to offer a rich usability experience, so media, and input, etc. must be tested accordingly.
- It is important to test mobile applications under different networks connectivity (both weak and strong) such as 4G, Wi-Fi, etc.
Differences between iOS and Android Devices
- There are numerous Android devices with plenty of different features available, so we often find it difficult to select one for purchase. With respect to testing, take for example Samsung S8 and Nexus devices, an application may behave differently in both devices. There is also a chance that layout may become distorted due to their individual hardware capabilities, and it is time-consuming for developers to make applications compatible for various devices. If we talk about iOS phones, the probability of error is low because they have a limited range of devices and almost all have the same resolutions and hardware capabilities.
- Android devices are widely available all over the world and it is a challenge for developers to design their code to maintain consistent performance. Even then, there is a chance that the application may perform differently.
- Another problem with different Android devices is that their manufacturers are different and we cannot upgrade software until they decide to upgrade their devices. The result is that not all users are able to enjoy the new features of the applications, and sometimes the hardware is not even compatible with new software, which subsequently forces the user to upgrade their devices.
Testing a mobile application can often seem easy at the start, but as soon as you start digging deep you will find that even a minute task is complex and difficult to test. It is the responsibility of a tester to make sure that not even a single scenario is missed out, and they should be intuitive enough to work on scenarios such as monkey testing, battery consumption, testing of devices on different networks by switching them, exploratory testing, etc. To be able to deliver a quality application after maximum test coverage, the organization should design a good strategy, make the right selection of devices, employ resources expert in various testing techniques (security, functionality, usability), and make sure that all necessary tools are available.