Yes, we will need your support with testing the project, please.
We have processes for testing and quality assurance, but the way that we think and use your app, is different to how you will. You defined the project, and you know what you want better than anyone, so you’ll probably use and interact with what we’ve built in ways that we couldn’t have predicted. >
Even if everything works 100% perfectly when we hand it over to you, you will need to check that everything works as expected to sign-off on the work with confidence that we've delivered the project to meet your specification.