A private notebook for the everyday details you log: symptoms, food, sleep, the walk you almost skipped. And the patterns hiding inside them. No streaks shouting at you, no badges, no dashboards. Just what we've noticed, in soft language, when there's enough to say.
Most health apps want to be your dashboard. Undercurrent wants to be your notebook. The one you actually open. We picked three things and refused to do anything else.
Symptoms, meals, meds, walks. Quick chips for what you log most. No required fields, ever. Half a thought is better than none.
Once you've logged enough events, Insights begins surfacing co-occurrences in your own data, phrased as tends to, never causes. You decide if it's signal or noise. Findings are described, not scored.
One tap exports an editorial Patient pattern summary: auto-numbered observations, frequency tables, time distributions, an event log. Sized for a five-minute appointment. No portal login on the other end.
In onboarding you pick a topic: My energy, a chronic symptom, mood, sleep, or something you'll name yourself. From there, the only job is to log when something happens. The app does the noticing.
Symptoms, food, meds, walks, mood. Quick chips for what you log most. No required fields, ever. Half a thought is better than none.
As you log, observations appear in soft language: Poor sleep appeared before 9 of 12 low-energy mornings. Tentative on purpose. You confirm, dismiss, or keep watching.
One tap exports an editorial PDF with observations, time distributions, and an event log. Black-and-white printable, sized for the time you actually get.
The Insights page is a single editorial column, hairline-divided, numbered i, ii, iii. Each observation leads with a soft-language statement, then the chart. None claim a cause. Here's a sample of what it surfaces.
"When our daughter started getting headaches, the doctor kept asking if we'd noticed any patterns, and we'd just shrug. We didn't have anywhere to keep track of the everyday details. So I built one."
The approach behind Undercurrent rests on three ideas, all backed by published research: that logging small things changes how you think about them, that smartphone diaries can identify real triggers, and that a shared summary helps the conversation with a clinician.
A review of 85 studies found self-monitoring and feedback to be the most effective techniques in digital health interventions for chronic conditions.
Clinical studies have confirmed smartphone diaries as an effective tool for trigger assessment, with daily tracking predicting symptom risk within 24 hours.
Visual diary summaries help patients and providers focus on actionable plans rather than vague recollections during short appointments.
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