Appium vs. Selenium

Can you now imagine the world without mobile apps or web apps? Obviously, no! Besides being go-to communication or information hubs, they have become fundamental platforms for performing everyday activities with just a few clicks, whether booking a restaurant table or paying your bills. 

With a highly competitive market, companies strive to deliver efficient apps without compromising on speed and quality. To ensure the app’s quality, they often prefer using the best testing solution. 

When it comes to test automation platforms, Selenium and Appium are two prominent players. Selenium is primarily used to test web apps across different browsers. On the flip side, Appium is used for testing all types of mobile apps – hybrid, native, and web apps – across different operating systems.   

This article aims to provide an in-depth comparison between Selenium and Appium. 

What Is Selenium?

Selenium is an open-source test automation platform comprised of various tools and libraries to enable browser automation. Simply put, it is a suite of tools to automate the testing of web applications across different browsers. 

With this tool, you can perform cross-browser testing and ensure that your web app functions correctly and consistently on different browsers. You can write and run test scripts in multiple programming languages, including Java, Ruby, NodeJS, JavaScript, C#, PHP, and Python.

Moreover, Selenium is extensible, i.e., you can seamlessly integrate it with other testing frameworks, such as TestNG, JUnit, Cucumber, etc.

Selenium offers a robust ecosystem of tools for browser automation, which includes:

Selenium IDE

It is a record and playback utility on the test scripts, which allows testers to export those recorded scripts in many languages.  It is available as an extension for Chrome and Firefox and as a desktop app. The scope of selenium IDE is limited, so the test scripts produced are not very sturdy or mobile.

Selenium WebDriver

It is a successor to Selenium RC and is the most important component of the tool suite. It provides a programming interface for the creation and execution of test cases. The web elements of web pages are identified by writing text scripts, and then the desired actions are performed on those elements. It performs more rapidly than Selenium RC by making direct calls to web browsers.

Selenium Grid

It is a crucial segment of the Selenium suite as it allows us to run tests on different machines against different browsers correspondingly. Tests can be run simultaneously on different machines running different browsers and OS.

This tool suite enables QAs to verify their web applications for cross-browser compatibility on both desktops and mobiles in an automated manner. Let’s understand this with an example.

Use Case Scenarios

Let us take an example to understand the use of Selenium. Consider that  a QA has to verify the functional test scenario of your e-commerce websites, which involves the following process:

• Click on the search bar
• Search for a specific product
• Add the product to the cart
• Click on Proceed to checkout

The above user scenario is tested manually on multiple browsers such as Chrome, Firefox, and Safari. This consumes a lot of time and is also inefficient. Hence, the Selenium Grid, a tool from the Selenium tool suite, is used. It simultaneously runs cross-browser tests on multiple machines and operating systems. This facilitates the automated testing process, eliminating manual efforts.

What Is Appium?

Appium was built on the idea that there shouldn’t be any requirement for SDK or application recompilation while testing native applications. It is an open-source project which makes design and tool decisions to encourage a vibrant contributing community. The goal for Appium is to automate any mobile app from any language and any test framework, with full access to back-end APIs and DBs from test code. You can write your tests with dev tools of your choice, using programming languages(Java, Python, Ruby, PHP, etc. ). The Appium server is scripted in Node.js and is compatible with leading client libraries like Java, Python, Ruby, PHP, and a few others. Appium is the most popular open-source framework for mobile app automation testing.

Use Case Scenario

Consider that you have developed a basic mobile application and performed manual tests on Android and iOS devices. Everything runs as expected. 

Now, you introduce a new feature into your app, which requires testing to ensure that it functions correctly and does not interrupt existing features. As a result, manually testing the app on both Android and iOS devices after every new feature is developed is inefficient and burdensome. 

Appium eliminates the manual efforts and automates tests against your application on both Android and iOS devices. 

Appium vs. Selenium: Key Benefits

Selenium

• Selenium is open-source and is very simple to use
• Provides compatibility with multiple operating systems like Windows, Linux, and Mac
• Gives developers or QAs the flexibility to write scripts in a programming language of their choice ( Java, Ruby, Python, etc.)
• Supports leading browsers like Chrome, Firefox, Safari, and Edge.
• Enables parallel testing
• Offers firm documentation support

Appium

• Appium is a free and open-source
• Enables automated testing of native, hybrid, and mobile web applications,
• Provides support for multiple programming languages (Ruby, Java, Python, etc.)
• Enables cross-platform (Android & iOS) testing on real devices, emulators, and simulators
• Enables cross-platform (Android & iOS) testing on real devices, emulators, and simulators

Appium vs. Selenium: A Detailed Comparison 

Let us now delve deeper into the differences between Appium and Selenium based on different parameters.

1. Concept of Design 

The concept of design behind Selenium was to automate the testing of websites and web apps across different browsers and their versions. It was designed to accelerate web app/website testing by automatically monitoring a browser’s behavior. 

Conversely, Appium is developed on top of the HTTP server using Node.js. So, if you want to use Appium, you must install and configure Node.js on your system. Appium facilitates the testing of mobile apps on platforms such as Android, iOS, and Windows. 

2. WebDriver 

As we discussed above, WebDriver is one of the components of Selenium. It is a collection of language-specific bindings to drive a browser. It lets you create browser-based regression automation test suits and distribute scripts across different environments. 

While using Selenium, you have two options to choose from to write automation test suites – Selenium WebDriver and Selenium IDE. On the flip side, Appium only supports WebDriver for test automation. It leverages WebDriver’s JSON wire protocol to operate Android and iOS sessions.

3. Platform Support 

Appium and Selenium are both cross-platform test automation tools. Selenium supports testing across a plethora of browsers and major operating systems. However, it does not support Android and iOS platforms. 

On the other hand, Appium supports testing of mobile apps on Android, iOS, and Windows platforms. 

4. Programming Language Support

Both Appium and Selenium support multiple programming languages to write test scripts. Java, Ruby, NodeJS, JavaScript, C#, PHP, and Python are a few programming languages in which you can write and run test scripts with Selenium. Though Appium primarily supports Java, it comes with bindings for other languages. 

Appium vs. Selenium vs. TestGrid: A Head-to-Head Comparison

Conclusion 

The choice between Appium and Selenium entirely depends on your project needs. If you want to automate the testing of mobile apps, Appium is a go-to choice. On the other hand, Selenium is a great fit for automating web application testing. 

However, if you are looking for a unified, end-to-end testing solution, TestGrid is an ideal choice. Its Real Device Cloud ensures that you use a combination of real Android and iOS devices and browsers to test your mobile apps and websites. In addition, it supports scriptless/codeless testing, eliminating the need for complex scripting and making testing accessible to both technical and non-technical teams.