Some people have said that its hard to concentrate around their computers or devices and this makes sense. Read or listen to the information provided take a couple of notes, and then go to a quiet place away from your devices.
At first, you might want to do the exercises a little bit faster, so that you can keep your attention in them. After a while, you'll be able to slow down and still keep your attention in the body and feelings.
You might wish to set a timer, and stay within the fifteen minute practice.