Does someone know how to use the site of a screen or the device (mobile) a user is using, so I can use it in an if statement when directing to another screen.
Or, does someone know how to scale a popup, that it is fullscreen on a mobile device?
when using jquery:
you can also check useragents possible.
with silkUI you can also check with some actions.
btw, popups on a mobile device is a no-no imho!