Now available in the App Store

Changelog


The Story Behind SefirahWatch

As Chol HaMoed Pesach began this year, I found myself looking at my Apple Watch and thinking: I want to see the Sefirah count right here, on my wrist, every day. I already have the Daf Yomi in a complication — why not the Omer? I could replace the battery indicator with something that would actually help me remember to count each night.

What surprised me was what I found when I went looking for an app to do this: nothing. There were a few paid options, but nothing free that offered a proper Apple Watch complication. So I decided to build it myself.

The catch? I'm not a software developer. I've never shipped an iOS app. But I've been having a lot of fun lately with AI-assisted development using Claude Code, and I figured this was exactly the kind of project to throw at it. I described what I wanted, asked questions, made decisions, and pushed back when things weren't right. Claude wrote the code. Eight days into the Omer, SefirahWatch was submitted to the App Store.

I think of myself as the product owner and Claude as the software development team. I couldn't have done this alone — but with AI as a collaborator, I was able to go from idea to shipped app in under a week. My hope is that this inspires others to scratch their own itch. You don't have to be a programmer to build something useful anymore. You just have to know what you want.


How It Works

SefirahWatch is built entirely with Apple's native frameworks — no third-party libraries, no external data sources, no servers. Everything runs on your device.

Sunset calculation is the heart of the app. Jewish law requires counting the Omer after nightfall (tzet hakochavim), defined as the moment the sun reaches 8.5° below the horizon. SefirahWatch implements the NOAA solar position algorithm entirely in Swift, using your device's GPS coordinates to calculate the precise moment of nightfall at your exact location each day. Your location is cached locally and shared between the app and its widgets — it is never transmitted anywhere.

The count itself is derived from the Hebrew calendar. All 49 traditional Hebrew count phrases — in both Ashkenazic and Sephardic traditions — are built into the app. There are no API calls, no internet dependency, no database. The app knows the Omer start date (16 Nissan 5786, the second night of Passover) and calculates everything forward from there.

iPhone widgets bring the count to your home screen and lock screen. A small widget shows the day number; a medium widget adds the full Hebrew count phrase. Lock screen widgets keep the count visible at a glance without even opening your phone.

The Apple Watch complication uses WidgetKit, the same framework that powers iPhone home screen and lock screen widgets. The app pre-calculates a timeline of nightfall times for every remaining day of the Omer and hands it to the system, which updates the complication automatically each evening — no app launch required. The circular complication shows the day number, the corner complication shows a progress arc across all 49 days, and the rectangular complication shows the full Hebrew count phrase.

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