This - really short - marketing video is a great example of how a customer video testimonial can create trust and help showcase software. Instead of showing full-screen screencasts, they extracted the most important parts of the app's user interface and laid them op top of the video testimonial. And all of that with a short and precise script in just 24 seconds total!

Customer Testimonial Video Script (72 words)

My team and I always had trouble managing our tasks until one of my colleagues found
You can see the task owner, what the deadline is, change the status, and it’s all in one place.
Inside each task, you can make comments, attach files, tag people.
It’s brilliant. It’s completely transformed the way that we work.
Honestly, I don’t know what we would do without it.