Simulators vs. Emulators: What's the Difference

Simulators and emulators are frequently used interchangeably in the world of software testing.

That makes logical up to a certain point. However, simulators and emulators are similar in many ways, and the distinctions between them aren't usually significant from a test engineer's perspective.

On the other hand, an emulator copies the functionality of the original device or system. The simulator acts like the object it's imitating.

What Is an Emulator?

An emulator is a software that emulates the target device's hardware and software on your computer. They accomplish this by employing binary translation to translate the target device's ISA (Instruction Set Architecture) to the one utilized by the computer you're testing on.

Each processor family writes its own set of principles in Machine Language, which they use to create their device configuration representing the device's functions and behaviors.

You can create a virtual environment for testing by converting the ISA of the target mobile device into your computer and simulating the actions of the target device.

However, the mobile device's near-native capabilities, which allow you to change physical sensors, geolocation, and other features, come at the penalty of latency.

Some of the most often used emulators for software testing are Android, Galaxy, and iPhone emulators (which is the erroneous name for iOS Simulator).

What Is a Simulator?

A simulator is a piece of software that allows your computer to execute programs designed for a different operating system. Unlike Android devices, which can be easily imitated, they are primarily developed for iPhone and iPad devices.

By sitting on top of the computer's operating system, iOS simulators imitate iOS and execute the relevant application within it. However, to use the iOS simulator, you must use Mac OS X because it requires Apple's native Cocoa API. This Cocoa API is required for the GUI, runtime, and various other tasks.

Because of this posture, developers must either work on the MacBook or virtualize macOS on their existing systems.

Simulators, in contrast to emulators, do not imitate hardware. As a result, while utilizing simulators for testing, certain capabilities such as cellular interrupts, battery utilization, and so on are not possible to study.

What’s the Difference: Simulators vs. Emulators

The significant difference between simulators and emulators is that simulators and emulators are two different beasts. Therefore, if you want to get the most out of each software testing tool, you need to know what distinguishes simulators from emulators and why you might select one over the other.

Simulator vs. Emulators

Below is the difference between simulators and emulators:

When to Use Emulators

On the other hand, emulators are extremely valuable for testing how software interacts with underlying hardware or a combination of hardware and software.

Do you want to discover if a firmware update will cause issues with your software? An emulator can assist you in figuring this out. Alternatively, you could want to know how your program performs when run on multiple CPUs or with varying memory allocations. Emulators can also be useful in certain situations.

When to Use Simulators

Simulators are most commonly used in software testing scenarios when you want to make sure that an application works as intended when interacting with other apps or environments.

You might wish to check whether an app can communicate data to other apps. A simulated environment will usually suffice because the underlying hardware configuration is unlikely to impact your application's data transfers significantly. Simulated testing environments are also useful to ensure that your application's interface shows correctly at various screen resolutions.

Conclusion

A simulator makes it quick and easy to build up a software environment for application testing without using real hardware. Emulators go one step farther by simulating both software and hardware combinations. When you need to test code quickly across a wide range of variants, both testing platforms are useful. However, neither is a complete replacement for real-device testing, which you should perform at essential periods, such as right before releasing software into production.