Functional Testing

Functional testing is a type of testing that seeks to establish whether each application feature works as per the software requirements.
Published March 19, 2022
Author R A Pitman
Read: 6 minutes

What is Functional Testing?

History of Functional Testing

The history of functional testing traces back to the late 1960s, with IBM’s evaluation of control program functionality by Gerald M. Weinberg and William Elmendorf. Over time, it evolved with the development of tools like Apache JMeter and IBM’s Rational Functional Tester, becoming an integral part of software development methodologies.

Why Do We Do Functional Testing?

As the age-old adage goes, "You only get one chance to make a good first impression," and this still holds true today. Launching your game or app with functionality issues that ruin the experience for players can often lead to bad reviews and just as importantly bad ratings. A recent survey polled users for how likely they would be to download a game that has less than a 4-star rating and as you can see the results were not promising.

Functional testing serves multiple purposes, including validating software performance, enhancing customer satisfaction, and preventing negative impacts on brand reputation caused by software malfunctions or bugs. If your game or application fails to perform against its basic requirements, it will more than likely not succeed in the marketplace.

Types of Functional Testing

There are different types of functional testing, including:

How to Do Functional Testing

To perform functional testing effectively, it’s essential to:

Functional Testing Strategies

Functional testing strategies include scripted testing, which provides a structured approach to ensure consistent test execution, and exploratory or Ad-Hoc testing, which allows testers to explore the application freely. Employing a combination of both strategies ensures comprehensive test coverage and reliability of the application.

Real-world examples and use cases demonstrate the importance of functional testing in identifying and resolving software issues before deployment. Test scenarios include installation testing, boundary value analysis, equivalence partitioning, error guessing, API testing, and regression testing, addressing common user actions and pathways.

Functional testing is a section of software testing that validates software against pre-determined specifications and requirements. This testing ensures that software is performing as both developers and end-users expect. These requirements are translated into test cases for testers to execute, ranging from responsiveness and navigation to connectivity and payment funnels. Functional tests often use a black box testing where the code is unknown. The tester uses inputs/outputs to validate functionality and any issues or “Bugs” are then reported back to the development team via bug tracking software.

Each of the issues or Bugs reported are categorized by the tester and given a severity. Although definitions can change across companies and teams the common standard is as follows

Example Bug

Severity Major

Description: This is a brief description of the bug. On level five of Flower Squad, the user encounters a plant that cannot be collected named the “Suntrap”.

Steps to Reproduce (STR):

  1. Start a new game of Flower Squad and proceed to level 5.
  2. Take the path marked “Highlands” at the end of the road leading out of the starting area.
  3. Once the crossroad is reached head left across the sunflower field and observe the giant sunflower growing at its center named “Suntrap”.
  4. Try to use your gather bonnet to pick and collect the “Suntrap” flower.
  5. Observe that although your character makes the digging motion to unearth the flower nothing happens and the plant remains in place.

Reproduction rate: This metric tracks how many times the bug is seen, if it was a one-time occurrence, or if it is 100% reproducible or repeatable. Reproduced: 10/10

Result: The Suntrap is unable to be gathered.

Expected result: The user should be able to collect all named plants and flowers in the game using the gather bonnet.


Functional testing cannot be overlooked or done without proper planning and expertise. It helps verify whether your application is working as intended and if not pours light on the issues that need to be addressed before launch. Even if an application passes non-functional tests and performs well, it has to deliver the expected results to be considered functional for end-users. It is sometimes left as an afterthought by some development teams or not given a high enough priority, however, after you poured your blood sweat and tears into bringing your dream game to live, you cannot afford to let it sink in a more of bad reviews due to poor QA!

XQA provides a dynamic functional QA testing solution comprising dedicated testers, a tailored test management platform aligned with client cycles, and a strategic testing process. Our approach is adaptable to your requirements, guaranteeing comprehensive test coverage to pinpoint any discrepancies between expected and actual performance. Curious about the capabilities of XQA? Reach out to explore how we can elevate your testing experience.

More Posts

Contact Us

How can we help?