Device Selection for iOS App Testing

One of the most critical issues in the mobile application testing process is test device selection. The choice of mobile devices is a core part of our strategic test planning or test definition that tracks success and ensures a high rate of adoption among our end users. There are more than 24000 types of Android and iOS devices in active use in the market, and new ones are added every day.

How should we choose the device that we will test from among so many devices?

Due to the rapid increase in mobile devices today, testing on all devices will be complex and expensive at every stage of the test. Therefore, since it will not be possible to run mobile tests on all devices in the market, it is necessary to choose a certain number of the most used devices in order to obtain the highest test coverage.

The Importance of Testing on Many Devices

A common and effective method for selecting iOS testers is to select the most popular devices based on usage rates. We should analyze the usage rates of the application and then choose the commonly used devices. When testing an app, there are many parameters to consider such as iOS version, hardware specifications, screen size, screen type. All these parameters are very important for mobile device selection for application testing.

So which device should we choose to test our iOS app and what are the parameters to consider when choosing the device for testing?

Let’s see together..

Parameters for Mobile Application Testing

Market Share

The device selection in mobile application tests should be chosen according to the popularity of the application in the market. Therefore, in order to carry out tests on the right devices, the most preferred devices in the market must be determined.

When we look at the usage rates of the Trendyol iOS application according to the screen resolutions on a device basis; We can say that the devices with the highest usage rate are iPhone 6, 6S, 7 and 8. We can see that the device with the lowest usage rate is the iPhone 12 Pro Max. Therefore, when we look at these data, we first check the application on the most preferred devices during the test processes. Then, we perform our checks on other devices, respectively. In addition, of course, we do not test iPhone 6, 6s, 7 and 8 devices separately during this process. Since the screen resolutions of these 4 devices are the same, it will be enough for us to check only one of them.

Screen Size and Resolution

Another parameter in device selection is to choose according to screen size and resolution. Screen size and resolution controls of devices are also very important to ensure User Interface (UI) compatibility.

The information of iOS devices according to screen sizes and resolutions is given below. Test coverage of applications can be maximized by selecting from the list below.

• 1170×2532 — iPhone 12 and 12 Pro
• 1242×2688 — iPhone XS Max and 11 Pro Max
• 1125×2436 — iPhone X, XS and 11 Pro
• 828×1792 — iPhone 11 and XR
• 1242×2208 — iPhone 6+, 6S+, 7+ and 8+
• 750×1334 — iPhone 6, 6S, 7 and 8
• 640×1136 — iPhone 5, 5S, SE
• 640×960 — iPhone 4 and 4S
• 2048×2732 — iPad Pro
• 1536×2048 — iPad Mini 2, 3 and 4 & iPad Air 1 and 2
• 768×1024 — iPad Mini, iPad 2

During the tests, we may encounter problems caused by fonts and points on small devices such as 5, 5S, SE and large devices such as iPad. In these cases, we can customize the point and fonts specific to these devices with the decision of the UX and Product teams.

Operating System Version Distribution

It is not enough to just specify the device for the tests. The application needs to be tested on different operating systems and versions. Therefore, the versions of the devices on which the application is used are also highly important.

In the table below, you can see the version distributions of the Trendyol iOS application. Since the application does not support iOS versions before 11.X, we do not prefer versions before 11.X for testing. When we look at the usage rates, we see that the high priority is in iOS 14.X. We check the application in 14.X, then 12.X, 13.X and 11.X, respectively. In addition, we check that the application is running smoothly in iOS new version updates.

In addition to these parameters;

• Find devices where the app often causes problems
• It should be determined what type of network connections the selected devices support

What is the difference between real device and simulator in mobile testing?

Simulators simply models a real system, i.e. it only exemplifies its operation, trying to create a lifelike environment. It helps to understand the operation of the system it exemplifies. The simulator is not a substitute for the real system.

Real testers are real handheld devices used to run the application to test its operation and behavior patterns. Testing on real devices gives us the most accurate test results. Because it allows testing almost all possible real-time scenarios. However, it is not preferred because of the wide variety of devices and the cost of real test devices. For this reason, testing on real devices is provided by making checks on a few devices.

I tried to explain device selection in Trendyol iOS Application Tests.

Thanks for reading! 👨🏼‍💻