I work a lot with the cruise ship industry, and one of the more interesting challenges we run into is that often there are user-facing systems that have to work without an Internet connection. I’ve designed applications that are supposed to work in a mine, or on a plane, and then later sync with the cloud, but building something that might not have a web connection for three days through the fjords  is a little different.

We’ve been looking into sending local notifications without any Internet access at all – from a server installed locally on the ship, to an app on a crew member or guest’s personal device. The basic idea is that an app, installed on the phone or tablet, can send a “local push notification” or “background push notification” to the operating system. Even if the app is not in the foreground, or the phone is asleep, the notification should wake the device up, and present the user with a message. This is exactly the same as a standard push notification (think Facebook or calendar notifications), but instead of using Apple’s push server, you are using an app itself to send the message. The problem is how do you trigger the app to do something in the background? The app has to wake up in the background, contact the local server, check for messages, download any available message or content, and then alert the user if it found anything.

There are a couple of ways to trigger a background application to do something for you. The two we looked into for our purposes were “Location Updates” and “Background Fetch”

Our limitation here is obviously the cellular modem will be turned off (Airplane mode) because there either is no cell tower around, or you don’t want your passengers paying international data roaming fees. There are other ways to trigger a background app action, but they mainly involve things like plugging in headphones, managing VoIP calls, and mainly Internet-requiring services. You can read more about the available options here: http://apple.co/29288f1

Option 1. The background fetch function appears to be the best option for this kind of app. This is something we’ve used in the past, but never had to worry about sans-Internet issues. The way background fetch works is the operating system puts your app into a queue of other apps asking for background services. The queue is processed based on which apps have the best efficiency. Apple does not really go into details, but it appears that the less data and the less battery your application uses in the background, the more frequently your app will be given background privileges (http://apple.co/291iAkd).

However, the problem here was we didn’t know exactly how efficient the application will be before we build it and start tuning it. So we built a prototype. While plugged in to a charger, it was able to receive messages every 10-12 minutes. Unplugged it was able to check the server only ever 20 minutes.

Option 2 (Augmentation). So in order to augment the inconsistent/unknown response time of the background fetch, we looked at the location updates. Location Updates are a way of triggering a background function when the device detects “a significant location change”. The idea is that if the phone detects movement that is “significant” (whatever that means) it will trigger your app. This is not exactly well documented but through some research and some experimentation it appears that “significant” means 1000 meters. This would be perfect for us, because seeing as while on a cruise you are probably moving 10 meters a second, we could have the app update every minute and a half. That would be an additional update cycle to cut down on the 10-minute maximum update cycle. The problem is that this measurement is tracked using the cellular antenna, and not the GPS! After a fair amount of banging our head on the desk, we gave up on Option 2.

As far as I know, planes and cruise ships are going to be relegated to the notification abyss for the time being. Without reliable Internet access, devices can’t get timely push notifications. The limitations on local push notifications while in airplane mode might be ok for notifying crew about training drills and passengers about dinner times, but it would not be reliable enough for emergency notifications.

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I help companies turn their technical ideas into reality.

CEO @Sourcetoad and @OnDeck

Founder of Thankscrate and Data and Sons

Author of Herding Cats and Coders

Fan of judo, squash, whiskey, aggressive inline, and temperamental British sports cars.

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The Internet Doesn’t Have Enough Love In It (And How We Can Fix It Easily)

In Technology

I’ve been thinking about all the wrong things when it comes to AI writing code.

Everyone else seems to be too. Job displacement. Security vulnerabilities. The ten-times-faster developer who now bills the same and delivers four times as much. These are real conversations worth having, just not the one I want to have right now.

The one I want to have is about teaching a six-year-old multiplication.

Here’s what I mean. Imagine you’ve been sitting with your kid every night for two weeks trying to explain multiplication. You’ve tried drawing rows of dots. You’ve tried songs (don’t judge me). You’ve tried the “just think of it as groups of things” approach that works for literally every other math concept but, mysteriously, not for your kid. Then one night, something clicks. You found the explanation, YOUR explanation, the one that worked for your actual kid with your actual kid’s brain, and it finally, beautifully, clicks.

Now imagine you could spend a Saturday morning turning that into a small web app. Not a startup. Not a SaaS platform. No login. No backend. No one’s going to hack it (there’s nothing to hack). Just a little thing that walks through multiplication the exact way you figured out it works, step by step, the way you’d explain it. You send it to the WhatsApp group for your kid’s class. Some of those other parents, also quietly losing their minds over multiplication, try it. And it helps.

You just made the world a tiny bit better. That’s it. That’s the whole thing.

Claude Code exists now, and a handful of other tools like it, and the reason I think this matters isn’t productivity. It’s access. The barrier between “I have an idea for something that could help people” and “I have a thing that helps people” used to require knowing how to code, or hiring someone who does, or talking a developer friend into your project over enough beers that their guilt exceeded their better judgment. Now it’s a Saturday morning and a good description of what you want to build.

The internet already has beautiful things in it that were built out of love. Free coding education for kids. Open-source video editors. Someone’s incredibly detailed home-brewing app with no monetization plan whatsoever. Artists making interactive experiences because they wanted to see if they could. These things exist because someone cared more about making the thing than making money from the thing. I think that ratio is about to shift dramatically in favor of the people who just want to make something good.

I’m not saying we should all stop paying for Salesforce (we should probably keep paying for Salesforce, there’s a reason that thing costs what it costs). I’m saying the category of software that was previously not worth building because it wasn’t commercial enough to justify the cost, that category just got a lot more interesting.

What’s in that category? Things like:

  • An app that helps beginning judo students understand the concepts behind a throw, not just the mechanics, because judo is where I learned confidence and discipline and I want other kids to find that
  • A private family memory vault (not Instagram, not Facebook, not anything with an algorithm deciding what matters), just a place where the people who love my son can send photos and stories somewhere safe, for him to open when he’s older (Maybe I’ll turn this into something?)
  • A system that reminds companies to send their employees gifts on the days that actually matter to them, because I know from running a company that it fills the cup of the person giving just as much as the person receiving (Thankscrate, if you’re curious, and yes, that one is turning into something real, but that is genuinely not why I built it)

None of those were commercial ideas first. They were just things I cared about.

I think the most interesting software that gets built in the next few years won’t come from developers moving faster. It’ll come from people who previously had no path from “I care about this” to “I built something about this,” and now they do. Parents. Coaches. Teachers. The person in your office who could explain that one complicated process better than anyone and has always secretly wanted to turn it into something.

The stakes are low. The bar to launch is low. The cost is low. The only thing required is that you actually give a damn about what you’re building.

So… What do you give a damn about?

Go build it. I still sometimes have to count on my fingers, but I’m told the app helps.