I want to make a simple popover (or modal) that allows a user to subscribe to a newsletter (of course only when a user clicks on "subscribe to newsletter", I don't want to be obnoxious). It'll be a small, vertically and horizontally centered overlay over the current page, and I'm thinking of using something like Simple Modal.
My question is (since I've heard that this isn't really recommended for mobile): will a modal be usable on mobile browsers, or are there better alternatives?
By the way, I prefer a modal and not a separate page because there is very little content. So a completely different page would look out of place to me. Also, signing up to a newsletter is something you do "on the side" I think, so it would seem logical to me to not take the user from the page he or she is visiting.