Maybe I’m not understanding your question but, yes, you just put them on your phone (as a wallpaper/screensaver) and carry it with you like you would a printed mandala. Of course, it helps to look at and interact with any mandala (printed or on device) every now and again.
I don’t understand what you mean by “laydown” or “what,” so I’m going to refer you to the threads where this has been discussed in great detail. Some of our friends have even made device-sized versions of the mandalas that you can use!