Meet BeatLog — The symptom diary your heart monitor came with

Medical

BeatLog

The symptom diary your heart monitor came with.

Every feature, from the first launch.

No account, no login, no cloud. Everything runs on your device and works fully offline — nothing in this post is hidden behind a wall.

What BeatLog does

BeatLog is the free, private, fully on-device symptom diary for anyone wearing a Holter, patch, or event monitor — built to do the one job that decides whether the test works: capture the exact moment a symptom hits.

When a cardiologist orders an ambulatory ECG (now worn 24 hours and up to 14 days with patch monitors like Zio), the patient is handed a paper diary and told to write down the precise time, what they were doing, and every symptom — palpitations, dizziness, chest pain, shortness of breath, near-fainting. The whole diagnostic value of the test rests on those time-stamped entries matching the device clock, so the cardiologist can correlate a symptom to the rhythm on the ECG. But paper diaries get lost, filled in from memory hours later, left undated, or never returned. A 2025 study found patient-reported symptom-to-arrhythmia correlation was accurate only about 22% of the time. Precise, real-time timestamping is exactly the gap.

BeatLog closes it.

What BeatLog does:

— One tap, exact time. Hit the big event button the instant a symptom starts and BeatLog stamps the device clock to the second — no typing, no recall, no reconstruction. — The AHA picklist, built in. Choose the symptom and what you were doing from a fixed list mirroring the standard paper diary: palpitations, dizziness, chest pain, shortness of breath, fainting / near-fainting; sitting, walking, exercise, eating, taking meds, sleeping. — Set the monitor once. Enter your monitor's start date and time and its ID at the start of the wear period so every entry lines up to the test window the cardiologist reads. — A clean report to hand back. At the end, get a chronological, printable list of every timestamped event and activity — ready to give the clinic in place of the paper sheet. — Works with any monitor. Holter, patch, or event recorder, any brand — there's nothing to measure, no heart-rate sensor, no pairing. — Gentle reminders. Optional nudges to keep logging through multi-day patch wear, all on-device.

BeatLog does not measure your heart rate or record an ECG — your prescribed monitor already does that. Its only job is the patient's only job: log the symptom timestamps and activities the cardiologist needs. It beats the lost-and-undated paper diary the AHA, Cleveland Clinic, and hospitals still hand out, and it owns the free slot the one paid competitor left open.

Free, no account, no network — your cardiac-symptom log never leaves your phone. For every patient sent home with a heart monitor and a paper diary.

A look inside

Tap any screenshot to open the full-resolution version.

What's inside

Log event — One tap stamps the exact device-clock time; pick symptom + activity from the AHA list
Monitor setup — Set the monitor's start date/time and ID once so every entry aligns to the test window
Diary timeline — Every event in chronological order against the wear period
Clinic report — Printable / exportable timestamped list to hand back at end of wear
Reminders — Optional gentle nudges to keep logging through multi-day patch wear

Why we built it

Patients wearing a Holter/patch/event monitor are handed a paper diary and told to write down the exact time and activity for every symptom so the cardiologist can correlate it to the ECG — but paper diaries are lost, filled in from memory, undated, or never returned, and a 2025 study found patient symptom-arrhythmia…

What makes it different

BeatLog is the only free, account-free, 100% on-device symptom diary built specifically to timestamp symptoms against a prescribed external heart monitor's clock. A one-tap event button stamps the device clock to the second the moment a symptom hits, using a fixed AHA-mirrored symptom + activity picklist, and exports…

Who it's for

Sandwich-generation caregivers, adult children of aging parents, and anyone keeping records for more than one person.

In one line: The symptom diary your heart monitor came with.

Try it

See the BeatLog app page for the full feature list, the info table, and support links.

Use BeatLog, found a bug, or have a feature request? Comments are open below — anonymous is fine.