Jack Groetzinger

Founder of SeatGeek.

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I quite like Markdown. When I need to send verbose thoughts, I often compose them in Byword in Markdown, copy/paste into a GitHub gist, and then send a link to the gist. For emails, it’s nice to get outside of clutter and distraction of the Gmail editor. In other cases, publishing in a gist is simpler and more elemental than writing a blog post, circulating a Google doc, etc.

But the GitHub gist formatting is imperfect for Markdown. Certainly not bad, but not ideal. Lines of text are too long. Vertical spacing between elements is at times confusing. There’s no mobile layout. GitHub can’t be blamed for any of this – gists are a free side-feature, and for the most part are awesome – but I wanted a simpler, more elegant way to present my thoughts.

So I created a little project called mkdown. Compose a gist on GitHub, then pass the gist ID in a mkdown URL, e.g....

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Beyond Flat

It seems mobile UIs are converging. Next month, millions of iPhone users will download a flatter version of iOS, one that doesn’t mimic real-life objects. Skeuomorphism used to be a huge red line that divided iOS and Android design [1]. Now iOS will be flatter, like Android. So it might seem like a great iOS design will work on Android too.

If only it were so easy! Depth and realism are important aspects of a mobile UI design, but they aren’t the only ones. Big, meaty differences between iOS and Android remain.

We’re currently building an Android app to accompany SeatGeek’s iOS app. It has been helpful for me to atomize the differences between iOS and Android’s UI guidelines and to look at how popular apps adjusted their UIs across platforms. This post is about what I’ve found [2].

Some Android apps feel like crude, literal ports of their iOS 6...

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From iPhone to iPad

Yesterday at SeatGeek we released a new version of our iOS app that includes iPad support. This was the culmination of months of designing and coding; I’m super-proud of what our team built. Huge credit goes to Matt, James, and Mladen, who led the charge.

When I sat down to wireframe this app, what I thought should be a simple exercise of translating views to a larger screen turned into a big challenge. Creating an iPad UI is hard, I learned—harder than it is for the iPhone [1]. Designing for the iPhone is wonderfully elemental. Imagine if websites had no sidebars—all you saw on a page was the most important, essential content. That’s what it’s like on the iPhone; it makes things easier.

But on the iPad, you have 8x as much screen space to fill. If only core content filled the whole screen on every view, you might end up with some odd-looking views. Consider the “performer” view...

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A/B Testing

We launched SeatGeek in 2009 at TechCrunch 50 (now renamed “Disrupt”). The elevator pitch was “Farecast for sports and concert tickets.” The site forecasted if ticket prices for an event would rise or fall so that a buyer could time her purchase optimally.

I diligently practiced the pitch. It was be the first time I’d be presenting to so many people. When it came time to present, we saw that Paul Graham would be one of our judges. Great news! We loved Paul Graham’s essays. I got on stage and delivered my spiel. It went pretty well–no major messups. Then time for the Q&A with the judges. We locked up. We’d practiced the pitch, but hadn’t prepared for what they asked us. Graham dismantled us. It was painful. It still is. I just forced myself to watch the video again and my chest now aches.

Afterwards, trying to ease my...

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Surprises when Designing an iPhone App

We launched SeatGeek’s iPhone app today. I’ve been creating websites for years, but until this project had never made anything native for a phone. As a first-timer, I was struck by some of the differences between web and mobile app design, which I’ll describe below.

First, a caveat: I worked on designing the SeatGeek app but not coding it [1]. What follows is relevant to web/app design more than development.

Designs magically look better on a Retina Display

Retina Displays are rose-colored glasses for Photoshop comps. Take an average design and put it on a Retina Display and it will look above average. Good designs become gorgeous. This discovery makes the whole process more fun. Designing for the Retina Display makes you feel like you have an extra 20% dose of talent. The effect never fully wore off for me; each time I beamed a design from Photoshop to my phone, I...

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Much ado is made about the utility of keyboard shortcuts. The more hotkeys you use, the more efficient you’ll be, right? Computer literate people are supposed to avoid the mouse as much as possible. Using a mouse to navigate through a menu tends to be slower than using a shortcut.

But why are button shortcuts limited to keyboards? Mice, after all, have buttons too. The problem is that most mice only have two or three of them. Since those buttons are used for core OS functions, it’s hard for them to also perform shortcuts.

But why do most mice only have 2-3 buttons? It’s a silly restriction! If you put more buttons on a mouse, you get more power.


Unless you’ve managed to transcend into some sort of hyper-zen keyboard/human symbiosis, you still spend part of your day with your hand on a mouse. And when it’s there, if you need to move back to your...

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Gmail as a Facade

When you create a new account, Gmail is blazingly fast. For most users, it stays that way forever. But for a minority of heavy users, Gmail gradually degrades towards slower and more painful speeds. Eventually doing simple tasks like sending an email or archiving a chain is downright glacial. Until a few weeks ago, glacial Gmail was part of my life.

The proximate cause of slowness is mailbox size. The alluring promise Google made when they first launched Gmail–that you never again have to delete any message–is not a reality. If a frequent emailer stops deleting messages, she’ll end up with a slow-as-hell mail app. I spent hours deleting as much of my inbox as I could, particularly emails with large attachements, but was still only able to get down to 11GB (I send a lot of email) [1].

I love Gmail as a mail app. Love the interface, love the shortcuts, love the...

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The Fastest Way to Get a Site Online

I am a big fan of Sinatra. I love the framework for its simple elegance, but I particularly love it because it’s Rack-compatible, and thus can be easily deployed to Heroku. Both Sinatra and Heroku are geared towards facilitating utter, brain-dead web development simplicity. Pairing them together is the fastest way I’ve found to get a website online.

The Heroku docs for deploying a Sinatra app are excellent, but perhaps make the process more intimidating than necessary for novices, if only because the page includes supplementary info for “pure” Rack apps and other Ruby DSLs. Last week I was helping a friend stick his toe in the water with web development. I wanted to show him how easy it could be to have his own site running on a real live URL. I showed him the Heroku docs, but his response wasn’t “holy shit, this is mind-boggling easy.” Which...

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The Value of Time

My co-founder and I have run our startup with religious frugality. When first looking for an office, we found a shared workspace that allowed us pay by the area, and we squeezed in folks for $160/mo per person. When traveling for business, I take the search-Hipmunk-and-choose-the-cheapest approach to finding a hotel. When hiring, we have a visceral aversion to using recruiters; engaging a recruiter seems like the ultimate expression of laziness. This sort of diehard cheapness is not original; there are plenty of startups that are even better at it than us. But recently I’ve been rethinking our approach…

Every person at every company has an implicit hourly rate of value they create for the business. Perhaps Bob, our traveling salesman, provides $150 of value for every hour that he’s working [1]. If Bob catches the flu and is forced to spend a day hunched over a...

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The Benefits of Arbitrary Questions

We recently hired a new office manager at SeatGeek. It’s possible to find good office manager candidates by posting on sites like Craigslist and Monster, but there’s a big signal-to-noise problem–a single Craigslist post can yield hundreds of resumes, many from unqualified applicants. The cost of posting on Craigslist isn’t $25; the true cost is your time.

Many applicants didn’t know anything about our company or the particulars of the job. Perhaps they did a search on Craigslist for “office manager” and applied to every job they found in rapid succession, hoping to get a few hits. These folks reduce the amount of time I can spend with folks who actually want to work at SeatGeek.

So during the past hiring process, I tried something a little unusual: I required that all applicants complete a short Excel challenge when applying [1]. Importantly,...

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