Situational intelligence for where mistakes are expensive — surfacing what's hidden in your data, and saying it only when it's true. We make @KELDapp.
Overland Park KS
Joined May 2026
- Tweets22
- Following21
- Followers3
- Likes12
A Living Field Guide: Putting Keld’s Catalog on the Open Web
biosignalai.com/a-living-fie…
A whole new look is just the surface, we went deep
Restorative Tiger
Keld built this whole video itself — voice and all — from your own sleep data.
Core Sleep and REM Sleep rise and fall together in your data, first caught 103 days ago and confirmed ever since. It's not a settled thing, though — the grip loosens and tightens week to week, coming and going rather than holding still. Keld shows that restlessness instead of smoothing it into a flatter story than the data supports.
See your own patterns: keld.us/activity/
Free to start, on the App Store now: apps.apple.com/app/id6759849…
#quantifiedself #signalinthenoise #applewatch #garmin #applehealth
Join the Beta of an App the iterates at light speed!
Keld is live on the App Store — but we're also testing what's next, and I want more real phones, real data, real skepticism on it before it ships.
We've got about 130 TestFlight seats open right now. If you're curious how the app behaves before everyone else sees it — bugs, rough edges, and all — I'd genuinely like your eyes on it.
👉 testflight.apple.com/join/fz…
Free. Works with any watch, ring, or app that feeds Apple Health.
We iterate at lightspeed...
v1.9.1 is live.
Your patterns now read in plain English — "Resting Heart Rate at Chapel Hill," not grid coordinates. A new Today summary lays out your day, no conclusions drawn. And the startup freeze is fixed.
Honest by design — Keld never says one thing "caused" another.
keld.us/your-places-named/
Incredible Update!
v1.8.2 is live.
The biggest Keld since launch. Four pattern categories on a rebuilt Pulse home. Two new Element classes — patterns at your places, and patterns that braid biology, weather, and place together. A new Forecasts tab with the Sun, Moon, and five naked-eye planets in your sky.
v1.7 proved the math. v1.8 built the experience around it.
keld.us/the-experience-built…
What a personal-biometrics model that stays honest about its own confidence actually looks like, end to end. New video from @KELDapp walks every panel of the Pulse page — for the people who already know the difference between a correlation and a confirmed pattern.
Keld v1.7.0 is live. Your saga, told — as a four-beat shareable video. Thirteen animal sigils. A rebuilt Pulse. A new Library. The honest-math Truth Gate woven through every reading.
Update in the App Store.
@KELDapp reads what's actually moving in your body's data — sleep, heart, energy, environment — and shows you your patterns, never an average of strangers.
Adding a small group of careful TestFlight testers to shape what comes next. Reply or DM.
Major improvements are coming soon to Keld
Here's one caption that works as-is on Facebook, Instagram, and X (paste with the cropped Keld card image):
I never told Keld to look for this — it found it. My walking speed and my step length aren't two numbers, they're one pattern. Faster pace, longer stride. Slow morning, shorter steps. My gait turns out to be a quiet, live readout of my energy.
keld.us/your-gait-is-a-live-…
The full essay — on latent variables, an unfashionable model of memory, and the instrument you infer into existence:
biosignalai.substack.com/p/t…
Which dissolves the sharpest objection — "unfalsifiable." It isn't. Every rung is an experiment: a question, an instrument added, an instrument built. Discovery widens. The standard of proof does not move. The objection becomes the research program.
From verified ground it can finally reach past the pairs — and tell you how to check it, cheapest first: notice a recurring "negative space" and ask you the open question (is there something on these days you're not recording?); or which instrument to add; or one to build.
A memory is only as honest as what it was raised on. Train it on lucky noise and it confabulates fluently. Train it only on what disciplined correlation certifies as real, and its baselines are true. Honest correlation isn't the filter at the end — it's the curriculum.
That thing is old and unfashionable: an energy-based model that, stripped back, is a memory — the Hopfield/Hinton lineage the 2024 Nobel in Physics honored. Recall is one operation: inferring the unobserved part of a pattern from the observed part. Exactly this problem.
But even a perfectly honest pair can't see the cause. If many signals move together, something is moving them — and that something is in none of the pairs. It lives in the geometry of all of them at once. You need a thing that can hold the whole shape.