Before the iPhone, before Android, before webOS, a revolutionary soap bar of a phone made it incredibly easy to get shit done. The Danger Hiptop, better known as the T-Mobile Sidekick, made the internet portable and affordable like no phone before.

It introduced cloud sync long before iCloud, popularized unlimited data and real web browsing on mobile, and made instant messaging and email a breeze thanks to its landscape hardware keyboard.

But the Sidekick doesn’t get enough credit for one physical button that tied the whole phone together: the Jump key. 

On modern phones, opening an app usually means tapping on a notification or hunting for the correct homescreen icon. To do, you have to see. Before the Sidekick, the hunt-and-peck was also harder than today: it meant physically pressing down with a stylus on a resistive Palm Pilot or Windows Mobile touchscreen.

But in 2002, the Hiptop’s Jump button turned multitasking into muscle memory. Every Sidekick shipped with both preset and programmable keyboard shortcuts, letting you “Jump” to any app.

I would type up my notes in the middle of college classrooms, Jump+B my way to the web browser to look something up, Jump+N back to my notepad, Jump+I to chat on AOL Instant Messenger with pals, then Jump+E to email the notes to myself at the end of class. My thumbs never left the keys. 

It was so convenient that I wound up taking most of my college notes on a Sidekick II – maybe all of them save Japanese.

Weirdly, T-Mobile didn’t make much of an effort to explain the Sidekick’s seamless task-switching potential. Real ones knew, but in the official user manuals, the Jump key is almost always described as a glorified home button. “Pressing JUMP takes you back to the Jump screen, your starting point for launching all the device applications,” reads a typical example. 

But former Danger director of design Matías Duarte, who went on to design webOS and the look and feel of Google’s Android, tells me Jump was never just a substitute for Home. It was designed to be chorded, pressing down multiple keys at a time to unlock its potential. “That was really where the power of it was, the thing that made it more than a home button, if you will.” 

“We worked on them, we relied on them,” he says of the keyboard shortcuts. Danger would file bug reports, set up meetings, chat in ICQ and email, copy them into notes, all from the Hiptop itself. “I lived on it because I was commuting by Caltrain up to the city every day,” says Duarte.

Originally, the Jump key was born to give you a way to jump in and out of mobile app notifications, which, back then, were pretty novel in and of themselves. “There wasn’t this concept of launching a program and quitting a program, it was you can jump to the notification and just jump back to what you’re doing.”

Unlike Palm Pilots, BlackBerrys, and flip phones of the era, the Sidekick didn’t kill apps when they were closed, he says — it had a “true multitasking architecture” where they kept on running in the background, connected to the internet. (Every phone does this today.)

“The state of the art of notifications always felt like they were these obnoxious lights that don’t respect you,” he says of the notification lights on other phones, “so it was important that they would pop up, banner up, and let you know who they were from. You could jump to it if you cared about it, or not if you ignored it. Together they were solving the problem of the user not being actually interrupted, but effectively multitasking.”

But it doesn’t surprise Duarte that the Jump button was marketed as something simpler, merely a way to get back to the homescreen where you could use the Sidekick’s dial to scroll through apps — because the button was genuinely supposed to do both. “The philosophy was that we wanted to make it really accessible, but we didn’t think that making it accessible made it less powerful.”

And it was called “Jump” to keep it simple. “We wanted to make something that was for normal people, where you didn’t need to understand any of these concepts of launching or quitting or multitasking.”

Jump wasn’t the only button that offered chorded keyboard shortcuts to Sidekick power users. You could cut, copy, paste, jump to a specific chat, or start a new email without launching the email client (and prefilled with the text you just copied!) by first holding down the Menu key.

Duarte says he struggled to justify adding the Menu button because he was trying to keep the phone simple — but Danger was also trying to keep it cheap, only giving you buttons and a one-dimensional scroll wheel instead of paying for a pricey (at the time) touchscreen. Repeatedly rotating and clicking a wheel to select each command seemed like a lot to ask of users.

“That’s why we needed the Menu button: so we weren’t always drilling in and out of everything,” he says.

Above: T-Mobile’s anime ad campaign for the Sidekick hinted at task-switching but didn’t explicitly show off shortcuts.

The Sidekick eventually died a sad death, abandoned by celebrities after Paris Hilton’s phone got hacked, shunned by some users after new owner Microsoft lost gobs of user data in a server failure, and replaced for people like me by Android (which, importantly, was created by some of the same people who launched the Hiptop).  

But many of Danger’s useful keyboard shortcuts live on to this very day. I found them waiting for me, like old friends, when I purchased the very first Android phone. Squinting, I spotted a tiny magnifying glass key on the T-Mobile G1’s sliding keyboard. I pressed Search+B, watched a web browser pop up, and grinned wide. 

For more on the Danger Hiptop, I recommend co-founder Joe Britt’s 2007 Stanford lecture on how it was built, Chris DeSalvo’s essay on its innovations, and retrospectives from MrMobile and TheUnlockr.