How does one go about shutting down an Apple Store in Manhattan without a computer virus? Duh: Just import the Jonas Brothers.

Tuesday night—the day the band’s third album, A Little Bit Longer, went on sale—the trio drew the masses to NYC’s SoHo Apple Store for a “secret” performance. And as EW’s go-to reporter for all things Jonas, I was sent downtown to take a listen. Okay, not to listen to the Jonas Brothers, per se, but rather, to listen to hundreds of girls screaming at the top of their lungs (while listening to the siblings Jonas).

Interestingly enough, the hour-long set wasn’t announced publicly until Tuesday morning, yet insatiable fans had been lined up since Monday night. The gals put their dedication on display: While the Brothers sang “When You Look Me in the Eyes,” one group of rabid fans held a sign that proudly screamed, “Here since 4 a.m.!” The crazy thing about all this, too, is that most of the attending fans had already seen the JoBros somewhere else during the week: The Apple Store show merely topped off a week of Jonasmania in NYC, highlighted by the band’s guest-hosting stint on TRL, a Good Morning America concert that drew 15,000 eardrum-busting fans into the city’s Bryant Park, and three sold-out shows at Madison Square Garden.

The Apple Store event, however, was intimate—and a fitting celebration at the end of a day that saw the new Jonas album strike No. 1 on both Amazon and iTunes by early morning. (Their first, out-of-print album, meanwhile, now fetches up to $350 on sites like eBay. We’re guessing that’s approximately three months’ worth of the average tween’s allowance.) Just 450 fans—including a Croc-wearing Harry Connick Jr. and his smitten daughter—were allowed inside (free of charge) for the 12-song Apple Store set, set-off by “That’s Just the Way We Roll.” Hands down, though, the screaming throngs—most of them wearing puff-paint covered t-shirts, while nearby adults inserted ear plugs—most enjoyed “A Little Bit Longer,” the ballad Nick wrote about his battle with diabetes. Several diabetic girls were in the crowd, as evidenced by shirts that proclaimed things like, “I’m Not Diabetic! I’m Sugar Challenged!”

The night’s final tune couldn’t have been more fitting: Summer anthem “Burnin’ Up” (yup, Big Rob was there and got his rap on, wearing a “Big Rob’s For Real” t-shirt) brought up the rear as two ambulances outside treated a slew of fainting gals, who had, predictably, overheated. Perhaps the Brothers need to remind their fans they’re just lyrics—not words to live by.

But PopWatchers, weigh in: Have you ever seen the Jonas Brothers live? What’d you think? Are the Jonas Brothers are ambulance-worthy? I mean, I’m talking about actual humans in need of medical attention here.

addCredit(“Jonas Brothers: Theo Wargo/WireImage”)