After James Moylan’s death in December, we were reminded again of the Moylan Arrow, the little arrow telling you which side of your car has the little fuel door:

I started wondering: what would be the conceptual equivalent of this in software? My best guess would be iOS offering to fill the one-time code from a recent SMS:

This is what it has in common with the Moylan Arrow:

• everyone benefits from it
• it happens all the time
• it solves an actual little (but not too little) frustration
• it’s there at the right place at the right time
• it is relatively low-tech (it’s not an overdesigned or an overengineered solution)
• once you know it’s there, you will love it forever

Curtosis on Mastodon unearthed the original 2019 Twitter thread from one the creator of the iOS feature, Ricky Mondello (link to XCancel), which I‘m reproducing here:

The idea for Security Code AutoFill came out of a small group of software engineers working on what we thought was a much more ambitious project. It wasn’t a PM, it wasn’t just one person, and it wasn’t what we set out to do initially.

It started as a small side idea we had while designing something very different. We jotted it down, tabled it for weeks, and then picked it up after the “more ambitious” project wasn’t panning out. It was hard, but I’m so glad we changed focus.

Even with a gem of an idea, it was still just an idea. Ideas are obviously super important — they’re necessary, but not sufficient. Here, the end result came from the idea, teamwork, and execution.

Years later, I’m still so proud of the team for making this feature happen. The team combined expertise from several areas to ship magic that worked on day 1, while asking nothing of app and website developers, without giving anyone your text messages. This still inspires me!

To every one of the folks who made this happen, I’m still in awe. Y’all are the best. <3

Addendum: FAQs
- “SMS is bad.”
↪ I know.

- “MITM.”
↪ I know.

- “FIDO is better.”
↪ It’s complicated, but acknowledged; I totally get it.

- “Android did it first.”
↪ Nah. Details matter. Privacy matters. And clipboard != AutoFill.

- *negativity*
↪ Not now. :)

I asked others on social and here are some other contenders I liked:

• The indicator that alerts you of Caps Lock when typing passwords
• Underlined letters in Windows
• Return key as an equivalent of the default action in a dialog box
• Proportionally-sized scroll bar handles
• Showing the current folder at the prompt in the terminal
• The quick link to your post after you post it
• The preview of the outside of the frame from the wide angle lens in the Camera app
• Holding space to move your cursor in iOS
• iPod automatically pausing music when you unplug the headphone jack

You can check out Mastodon and Bluesky threads for more, if you are interested.