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Practical Ways to Use QR Codes

by Glenn Fleishman

Let me come clean: For way too long now, I’ve been excited about the 2D optical code format called QR Code [1]. I even convinced TidBITS to put one on every article page for a while. There’s just something wonderful about using a digital device to access hidden information in an “analog” form, whether it’s printed on a poster, in a magazine, or on a billboard — or shown on someone else’s mobile device.

QR codes encode data as a set of error-resistant areas of black and white. The format is designed to work with poor printing, low light, and fuzzy scanning. It’s resilient! As a result, its information density is relatively low, but most of the time QR codes contain just a URL, a calendar appointment, a Wi-Fi network connection’s details, or the like, so they don’t need to take up much space. You couldn’t use a QR code to encode the text of “Moby-Dick,” though you might create a QR code that has the URL to reach Project Gutenberg’s download page for the tome.

[image link] [2]

I like to think of QR codes as “analog-to-digital glue,” because they’re useful in situations in which it would be hard to get some data into your mobile device. Google has long taken advantage of this with Google Play, enabling developers to generate a download link as a QR code for the Play app to scan. (Oddly, Android only integrated QR code recognition two years ago. Motorola had built it into their smartphones’ camera app previous to that.)

You can imagine how excited I was when Apple announced that iOS 11 would include automatic QR code recognition in its Camera app — primarily because of the need for it in China. If you haven’t visited Japan in the last 15 years or China in the last 3, or read about how people in those countries use technology, you might be unaware of just how widely QR codes are embraced in those countries.

Will that happen elsewhere in the world now? I hope so, but for practical reasons, as I’ll explain.

The Current Heavy Use of QR Codes -- Japan is where QR codes were developed and promoted by handset makers, cellular carriers, advertisers, and publishers, leading to early high adoption back in the early 2000s. The QR Code format was developed by Denso Wave [3], which agreed not to enforce its patent.

More recently, Chinese merchants started using QR codes [4] as a cheap form of touchless payment. Instead of expensive NFC (near-field communications) terminals and a need for smartphones with that tech built in, two giant Chinese Internet and e-commerce companies — WeChat and Alibaba — added QR codes as the payment glue in physical stores. A customer either scans a QR code at the retailer’s register and authorizes payment, or they can present a QR code on the phone that the retailer scans to accept payment. In the United States, Walmart has caught on to that concept — see “Walmart Pay Is Better Than You Might Expect” (18 July 2016).

But most uses of QR codes in America and Europe hide their full potential, resorting to simple apps that merely display a QR code for a boarding pass or a rewards club card — Apple’s built-in Wallet app does this. Plus, requiring users to download and launch a special app to scan QR codes hurt adoption by being too high of a barrier to widespread use.

But this obstacle falls away with automatic recognition. As of iOS 11, if a QR code appears anywhere in the Camera app’s field of vision, you’ll get a notification describing the kind of thing encoded. Tap the notification, and the iPhone performs the correct related action, opening a Web page or prompting to add a calendar entry. For a preview, pull down on the notification. (You can disable Scan QR Codes in Settings > Camera if you don’t like this automatic scanning, but it’s easier just to ignore the occasional scanned code.)

[image link] [6]

What’s interesting about QR codes is that they encode text but don’t define what should be done with it. That’s entirely a function of the scanning app. Over the years, people have invented more and more uses for QR codes, and iOS 11 supports nearly all of them, as do Android and most third-party QR code apps. Most of the forms of information rely on the URI (Universal Resource Identifier) style format of protocol://addressing, as in a URL, which is http:// plus the domain name, path, and variables.

The main types of data that the QR Code format can encode are:

[image link] [8]

You can generate all these types of QR codes for free via any number of Web sites, like QR Code Generator [9]. Some sites, like QRCode Monkey [10], let you customize the design without harming the QR code’s recognition; there’s so much error correction built into QR codes that large portions can be replaced with graphics. Once you generate a QR code on these sites, you can download it in PNG and other graphic formats. Most also support vector formats (like EPS, SVG, and PDF) for prepress or to use as a browser- or JavaScript-scalable element on a Web page.

[image link] [11]

For encoding private information, such as a Wi-Fi connection code that contains your network password, I recommend JavaScript-based generators instead of Web sites that require a round-trip to a server. I use Pure JS WiFi QR Code Generator [12] for Wi-Fi codes, which does what its name promises: the information never leaves your browser.

You can also turn to an iOS app. I like Visual Codes [13] by Benjamin Mayo for simple uses. It generates codes onscreen for free and lets you share and print them with a one-time $1.99 in-app purchase. Using an app is also a good option for creating QR codes that contain sensitive information.

Now, how might you use these QR codes in practice?

A Visual Shortcut in a Box -- You can deploy QR codes anywhere that you know someone would have to type something in, to help them bypass that effort, while also making it more likely that they will complete a task or capture additional details. Here are some suggested uses:

Keep in mind how far someone’s phone will be from the QR code, relative to the information density in the code. The more information you encode, the more detail the camera has to distinguish. That’s no problem close up, like in a book, a business card, or a flyer. When creating QR codes meant to be scanned from far away, as with a billboard or store signage, consider using a URL shortener to make the blockiest, lowest-density QR code possible.

[image link] [17]

Wide Support Will Generate Emergent Uses -- I’ve listed a few ways you could deploy QR codes, but I’m sure we’ll soon discover other alternatives people come with for QR codes. With iOS 11, hundreds of millions of people suddenly gained access to QR code scanning. And we Apple users aren’t alone: Android 6.0, released in October 2015, added native QR code scanning.

Now that nearly everyone with a smartphone made in the last few years can scan QR codes without needing a special app, it’s time to put QR codes to use anywhere you need to reduce the friction of passing information from the real world to a digital device.