Only desktop. I like to see good pictures on big screen, I can zoom in and zoom out without any problems. I don't wear glasses however phone screen is too small for me to see the details and also many websites send smaller pictures for mobile users which makes zooming in pointless.
If I'm buying something important, I prefer to do it for my laptop, where bugs are less likely to occur. If it's for normal shopping, the mobile is just more practical :)