Building UpnOut, an NFC alarm app, in a day
An alarm that only stops when you get out of bed and scan a tag. Why I built it, how one AI tool took it from idea to a working iOS app in a day, and why I am putting it in the App Store.
The idea is simple. You set an alarm. You put an NFC tag somewhere away from your bed. The alarm only stops when you get up and scan it.
I had seen a few apps like this start to appear. Most of them had the same catch. To use them, you paid to have their NFC tag posted to you. A tag is a small, cheap sticker. Any tag will do the job. That felt like the wrong place for the friction to be.
So I built my own. In a day.
Why a day
New models are arriving every few weeks now. Grok had just been added to Cursor. Each new model claims to do more of the work on its own.
I wanted to test that properly. Not a demo, not a to-do list. A real iOS app that talks to real hardware. One tool, pushed as hard as I could push it, for one day.
How it was built
I built it with Grok in Cursor, which I had never used before, and let it run the whole app. It is written in Swift, for iOS. I gave it the idea and kept asking for more, rather than stepping in and writing the code myself.
The NFC part is the bit I could not test on the day. I ordered a pack of tags from Amazon, and they were not going to arrive until the next morning. So the app was written against hardware I did not have yet.
The tags arrived the day after. I stuck one up, set an alarm, and scanned it. It worked first time.
The tags arrived the next morning. It worked perfectly.
Then the fun part
With the app working, I got into the part I enjoy most. Branding.
UpnOut needed to be loud. It is the first thing you see in the morning, and it has one job. Bright yellow, heavy black type, and a line that says exactly what it does:
One alarm. One tag. You're up.
The app itself is quieter. A list of alarms, each named after where its tag lives. Bathroom at 7:00. Kitchen at 8:30. The name tells you where you are walking to.
I pulled all of the assets together in the same burst. Logo, screenshots, the lot.
Why I am publishing it
I showed it to my partner. We talked it through, and the question became an obvious one. Why not just put it out there and see what people think?
There is a more personal reason too. I have ADHD. Some days, getting out of bed and actually functioning is hard. Not hard in the way an early start is hard. Hard in the way that a snooze button becomes the whole morning.
A tag in the kitchen does not fix that. It does remove one decision. You do not have to choose to get up. You have to turn the alarm off, and the only way to do that is to be up. Lowering that barrier is the point of the app. If it helps me, it will help somebody else.
Where it is now
UpnOut is in the cleanup phase. The core works. I am tidying the rough edges from a one-day build before it goes to the App Store.
The bigger lesson is about the tools. A day was enough to go from an idea to an app that works with real hardware, built in a tool I had never used before. That was not true not long ago. The part that still took me was the part I wanted to do myself: deciding what it should feel like.
