As an application integration engineer, you'll use several different applications, tools, and methodologies to perform your job. The interviewer will likely ask you about these to confirm that you are familiar with them and see whether the tools and applications you use align with the ones their organization is currently employing. This should be an easy question for you to answer since you use these items every day. It would be helpful if you researched the organization to determine what tools and applications they use to either align your answer to their current environment or be aware that the ones you use are not the same ones they use.