Simulators, Emulators, or Real Devices: Which is the Best for Mobile Testing?

Software testing to find bugs is an integral part of the overall software development process. You make sure users will not have problems like navigation hiccups, breaks in payment processing, or issues with signup forms through software testing.

Independent software testing teams will build cross-browser testing or browser compatibility testing strategies. But you need to decide on the testing environment early on. The environment and device can make a big difference in your results.  Mobile testing has three options to choose from simulators, emulators, or real devices. Or, you can mix and match any of these three. 

All of these testing environments offer benefits but also some drawbacks.

Let’s learn about the differences, advantages, and disadvantages of testing with simulators, emulators, and real devices.

Simulators, Emulators, or Real Devices: Which is the Best for Mobile Testing?

Differences Between Simulators, Emulators, and Real Devices

Testing on real devices means you use the same mobile handsets that your users would use to test the behavior and functionality of your website or app. In real device testing, independent software testing teams or in-house software testing teams use actual mobile Android phones, Blackberry, iOS, tablets, or iPads to test an application and ensure it will run smoothly for your customers.

Simulators and emulators are virtual devices or software programs on a computer that provide the same functionality as a real phone.

Let’s learn about the differences between a simulator and an emulator:

Simulator Emulator
Simulates the internal state of a phone. Emulates or mimics the outer behavior of a phone.
Testers prefer simulators to test the mobile’s internal components like firmware, internal hardware, etc. Emulators are used when a team wants to test a mobile’s external behavior like transactions, calculating, etc.
It’s a partial re-implementation of the original software. It’s often a complete re-implementation of the original software.
Written in a high-level language. Written in machine-level assembly language.
Difficult to debug. Often easier to debug.

What are the advantages of simulators/emulators?


Virtualization of a variety of devices and OS allows them to validate multiple platforms easily. They also are useful in cases that require specific OS combinations and devices.


Both local and cloud solutions are substantially cheaper than real devices.


When testing on virtual devices, you can always start from the same state. However, if you want to do it on a real device, you may need to do a factory reset, which requires more effort.

What are the advantages of testing on real mobile devices?

Better UI Validation

To validate the accuracy of the UI, you should test it on real devices. You can easily find usability issues with real device testing.

Real Thing

If you want to test whether your application is working or not true, use a real device. While some tests may pass on virtual devices, you can only test certain problems on real devices.

Accurate Performance Testing

Testing on real devices offers you more reliable and accurate performance measures. 

What are the disadvantages of simulators/emulators?

  1. If you want to validate your application’s performance, simulators and emulators are not always the best testing solution.
  2. They are mostly suitable for some types of functional test case executions.
  3. They do not support certain applications.
  4. They do not support all kinds of mobile app testing.

What are the disadvantages of testing on real mobile devices?

  1. Real devices are more costly than virtual devices and lower your profitability.
  2. Acquiring all the mobile devices available on the market can become a big strain on your budget and timeline.
  3. When you use real mobile devices for unit testing and similar purposes, they could be harder to connect with IDE. That can lead to problems in debugging and may also delay your project and overextend your budget.
  4. Your testing efforts may be hampered if the mobile devices are not secure enough. Yet, making them more secure may increase your expenditures.

Conclusion: Deciding Which One to Use

When it comes to independent software testing, you should understand that it’s not an either/or proposition. You’ll have to find the right balance through continuous deployment and integration between virtual devices and real devices for your best testing results. For any mobile app testing, make decisions on a case-by-case basis. It also depends on where you are in your software development cycle. 

If changes affect both UI and mobile app architecture, it’s best to use both real and virtual devices. Start slow with a few devices and gradually scale up your testing operations.  If you’re looking for more information regarding software testing, contact us.

Frequently Asked Questions

What is a Real Device in Mobile Testing?

Real device testing means you test your application on an actual mobile device. It is very useful to understand how your application will work in the user’s hands.

What is a Virtual Testing Device?

A virtual testing device is a software program that provides simulation for testing the important features of an actual mobile app. It mimics real devices and is cost-efficient, but it lacks accuracy and reliability. Virtual testing can be done through either emulators or simulators.

What is an Emulator in Mobile Testing?

Emulators emulate the experience of a device. They mimic the hardware, device software, and the OS of the actual device. They tend to be better at mimicking the device’s functionalities.

What Is a Simulator in Mobile Testing?

Simulators mimic the internal behavior of a device without considering its hardware.