Dropping-by with a resume might work. The reason most people don’t want to try it is that, nowadays, most employers have a “Don’t Call Us, We’ll Call You” way of thinking. They want us only to submit an application online. Then, they don’t want to hear from us. If we follow-up with a phone call, they become annoyed and say, “If we’re interested, we’ll contact you.”
So while I continue to say that delivering a copy of your resume in person is a nice touch that will almost certainly differentiate you from the rest of the pack, you should certainly still go ahead and fill out the online application. Hiring managers will need that done before they can schedule a formal interview.