The choice of tools often depends on the object and testing requirements to test cases, because testing tools can not support everything the technologies used in application development. That is, the choice of instrument is reduced to the commonplace method of trial and error. As a result, we often select a few tools to test the application. For example, GUI tools, we check on Mercury WinRunner, backend processes – using "java based test tools" or other tools. Key aspects of choosing a test automation tool discussed in the section "How to automate?".
Consider the tools for automated functional testing of different manufacturers: