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 cruise lines turn their technical ideas into reality. I'm experienced in all stages of innovation and technology management. I've also been programing since I was 8 years old, and have somehow retained the ability to have normal human interactions. Occasionally I speak about how Industrial Psychology and Neurophysiology can be interrogated with IT and systems management, because I spend a lot of time thinking about the subject, as strange as that may seem.

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How to Land Your First Tech Job: Or at least what I will tell you

In Technology


Ah, the age-old question that haunts every college graduate’s dreams: “How do I get a job?” But not just any job. A job that doesn’t involve asking, “Would you like fries with that?” unless it’s a cheeky Slack message to your new tech team while deploying code (because, let’s face it, multitasking is key).

So, you’re fresh out of college, armed with a degree, and ready to conquer the tech world. But there’s a catch – everyone wants experience, and you’re fresh out of that. It’s like needing a job to get experience but needing experience to get a job. A real chicken and egg situation, except less philosophical and more annoying.

Now, before you start sending LinkedIn invites to every CEO with a pulse, hoping one of them will notice your enthusiasm (or desperation), let’s talk strategy.

1. Start a Blog – No, Seriously

First things first, start a blog. I give this advice to everyone, and you’re not going to take it, but I will keep trying.

“But I’m not a writer,” you protest. Well, guess what? Neither are most of your competitors when it comes to that job interview. But here’s the thing – writing helps you articulate thoughts, share knowledge, and most importantly, shows you’re committed. Write about what excites you in tech. Dissect the latest AI breakthrough, or maybe just rant about why tabs are better than spaces. It’s your stage. It’ll also help you greatly when interviewing. If you’ve actually researched and forced yourself to write about a topic, it’s WAY easier to talk about it.

If the thought of cranking out 500 words twice a week makes you sweat, consider this: if you can’t commit to a blog, how will you commit to a job? Harsh but fair.

2. Ship Something… Anything!

Next, if you’re a coder, designer, or any species of maker, you need to create something and get it out into the world. A portfolio is great, but a product is better. It doesn’t have to be the next Facebook. Heck, it can be a to-do list app that makes a satisfying ‘ding’ sound when you check off an item. But it shows you can see a project through from start to finish. Plus, nothing beats the thrill of seeing your creation out in the wild, even if it’s only used by three people (including your mom). And three users is way more than what most juniors come to interviews with.

3. Polish That LinkedIn Profile

Ah, LinkedIn, the worse MySpace of the professional world. It might not be the most exhilarating social network, but it’s where the grown-ups and LinkedIn Lunatics go to humble brag. So, get your profile in tip-top shape. Showcase your blog, add a professional photo (no, your beach selfie doesn’t count), and maybe sprinkle in a few insightful comments on posts. Show the world you know how to play the game. It’s only for show as a junior, and everyone knows it, so don’t go overboard.

4. Read. Then Read Some More.

While not the world’s biggest Jim Mattis fan, I got a bit of a kick in the pants after reading his Call Sign Chaos: Learning to Lead. In it he said “If you haven’t read 100 books on the field in which you claim to be an expert, then you are functionally illiterate.” That was a bit of a wake up call for me as a CEO. So if you’re a junior, lets make that rule “If you haven’t read at least five books about your chosen profession, you’re not ready to be a junior anything.” It’s a bold claim, but let’s face it, you’re competing with people who live and breathe this stuff. Catch up.

5. Network, Even If It’s Painful

Finally, networking. Yes, it’s awkward. Yes, it feels like speed dating but with business cards. But knowing what’s happening in your field and who the players are is invaluable. So, go to those tech meetups, chat with people, and yes, maybe even endure a few boring conversations about someone’s revolutionary blockchain startup. Try and meet one or two people who know me before you reach out to me. Then we can have someone to gossip about, and it’ll feel more personal. Tampa has a few good tech networks that throw decent, free events where you can find people who know me. Check out Tampa Bay Wave, Embarc Collective, and Tampa Bay Technology Forum.

And there you have it. Five steps to improve your odds of landing a job in tech. Most won’t follow this advice, but if you do, you’ll be ahead of the game. And who knows, one day, I might be asking you for a job. Or at least, for some tips on my blog.