2026Personal experimentFree Habit Tracking App on the App Store
Interaction Design,
Agentic iOS Engineering
HEIF10, Rec. 2100 PQWritten with Claude Opus 5
If the text above doesn’t glow significatly brighter on your current screen,
please come back to on iPhone 12 Pro or newer, MacBook Pro
or other HDR capable screens to see the effect.
I first saw this effect in an ad on LinkedIn. Companies had worked out that an HDR image renders physically brighter than everything around it in a feed. I could not not look away.
It works: The eye has no defence against excessive brightness, and nothing in the feed can outcompete sheer light for attention.
Naturally, I wanted to see whether that same effect could pull my eyes toward something I had actually chosen.
Light is not a colour. iOS will not draw a color brighter than white.
every glowing mark in this app is a "white HDR photograph".
10-bit HEIF in Rec. 2100 PQ encodes absolute luminanace and is then clipped into shape.
No streaks. Nothing to protect, nothing to lose, and no reason to open the app on a day you have already finished.
The widget is the product. Tapping it gets you a bigger version of the same thing, not a different visualisation of same data.
After set-up you will not be leaving the home screen at all.
The app and the widget complete differently, on purpose.
The app's ring closes on a spring.
The widget cross-fades, because a widget is a sequence of stills and timeline entries do not arrive at the rate they were sampled at.
Who built it?
I directed it. Most of the code was written by Claude Opus 5 under instruction, and the commit log says so in git's own terms rather than in a footnote: Claude is the author of a commit it wrote, and I am the committer. The practice only works if it is accurate in both directions, so the commits I genuinely wrote stay mine.
So what does the designer actually do?
I stopped writing tickets. An agent interviews me, and the interview becomes the issue — written as prose that argues for the change, in the same voice as the rest of the repository. Judging and deciding is the work.
Free on the App Store
View in App Store