They're a bit larger on my monitor, but only a bit.
Frankly, the company I'm using for this is not very easy to communicate with and I've been unable to get information from them on how to make the video windows larger on a normal computer monitor. They keep telling me that it's something I control, and I keep asking them how do I control it. That's been going on for a year.
They are much larger on an iPad: they take up the entire lower half of the screen and can go full screen. I am hoping that the app we're going to launch in a month or so for Android tablets and the Kindle Fire will be as nice as the one we have for the iPad.