Why Is Regression Testing for Mobile Application is Important
                     Why Is Regression Testing for Mobile 
Application is Important?
Regression testing for mobile applications is a kind of testing that is performed to check that 
a software update does not impose a poor impact on the existing functionality of the product.
This is to make sure the product runs fine with updated functionality, bug fixes or any 
difference in the existing feature. Earlier completed test cases are re-executed to check the 
result of the change.
Regression Testing for mobile applications is a Software Testing class in which test cases are 
   r e  -  executed to verify whether the earlier functionality of the application is working fine, and 
the new changes have not included any new bugs.
Why the Regression Test?
Regression is initiated when a programmer fixes any flaw or adds a new code for new 
functionality to the system. There can be many dependencies in the recently added and 
existing functionality.
Most of the time, the testing team has the job to check the last minute variations in the 
system. In such a condition, testing only affected application area is necessary to complete 
the testing process on time by covering all the major system aspects.
This test is crucial when there is a constant change/improvement added in the application. 
The new functionality should not negatively influence the existing tested code.
Regression is needed to find the flaws that occurred because of a change in the code. If this 
testing is not performed, the product might get significant issues in real-time, and that 
certainly can lead the customer into a problem.
While testing any online website, a tester reports a problem that the Price of the Product is 
not displayed accurately i.e. it shows lesser price than the actual cost of the product, and it 
requires to be fixed soon.
Once the developer fixes the concern, it requires to be re-tested, and Regression testing is 
also required as checking the price at the reported page would have got fixed but it might 
be showing an incorrect value at the summary page where the total is shown along with the 
additional costs or the mail sent to the customer still has the inaccurate price.
Once the developer fixes the concern, it requires to be re-tested, and Regression testing is 
also required as checking the price at the reported page would have got fixed but it might 
be showing an incorrect value at the summary page where the total is shown along with the 
additional costs or the mail sent to the customer still has the inaccurate price.
Now, in this case, the client will have to bear the loss if this testing is not done as the site 
determines the total cost with the wrong price and the same price goes to a customer by 
email. Once the customer accepts, the product is sold online at a lower price; it will be a 
loss for the customer.
Types of Regression Testing
Given below are the various types of regression testing :
Unit Regression
Partial Regression
Complete Regression
1) Unit Regression:
Unit Regression is performed during the unit testing phase, and code is tested in privacy, i.e. 
any dependencies on the unit to be tested are barred so that the unit can be tested 
personally without any mistake.
2) Partial Regression:
Partial regression is done to confirm that the code runs fine even when the alterations have 
been done in the code and that unit is integrated with the unchanged or already existing 
code.
3) Complete Regression:
Complete Regression is done when an alteration in the code is done on a number of 
modules and also if the change impact of a change in any other module is uncertain. 
Product as a combination is reverted to check any modifications because of the changed 
code.
Conclusion
Regression testing is one of the crucial features as it helps to deliver a quality product by 
making sure that any variation in the code whether it’s small or large does not affect the 
current or old functionality.
A lot of automation tools are handy for automating the regression test cases. Though a tool 
should be picked as per the Project need, a tool should have the capability to renew the test 
suite as the Regression test suite requires to be updated frequently.