Lens HRV

about

description

Lens HRV is an Android app that measures <b>heart-rate variability</b> — how much the time between your heartbeats changes from one beat to the next, measured in milliseconds. It uses Photoplethysmography (PPG), a simple optical technique that detects tiny changes in blood flow through your fingertip using only your phone’s camera and flash. Completely non-invasive and requires no extra sensors. <b>Why HRV matters</b> Heart-rate variability is more than just a heart measurement. The small changes between your heartbeats come from many processes happening in the body at the same time. Your heart does not work alone. It is constantly interacting with the rest of the body — the nervous system, the lungs, hormones, temperature, the immune system, digestion, circadian cycles, emotions and more. HRV works like a microscope that lets us observe that interconnected network. <b>What makes Lens HRV different</b> Most HRV apps today work like closed boxes. They are usually paid, require expensive extra sensors, and only show you the final numbers they decide to calculate. You rarely get access to the raw signal. Many of them also oversimplify the body’s state into a single score or color. Lens HRV is completely open source. Every algorithm it uses comes from publicly available, peer-reviewed research. The focus is on classic digital signal processing instead of heavy artificial intelligence. This keeps the app lightweight, understandable, and able to run on a wide range of devices. All data is processed directly on your phone — nothing is sent to the cloud. You keep full privacy and full control. The app does not offer “readiness” scores. That kind of metric is considered too complex and often oversimplified. Instead, Lens HRV focuses on clear and simple measurements. The goal is a frictionless tool that is accessible to everyone. <b>How it works</b> Place your index finger over the camera lens until the preview turns a deep red. A short calibration starts the recording. Keep the finger still. When it ends, the full signal is processed offline. The preset is meant for normal indoor conditions. <b>What you get</b> Time domain: <b>Heart Rate</b>, <b>RMSSD</b>, <b>SDNN</b> and <b>Stress Index</b>. Frequency domain: <b>Total Power</b>, <b>LF</b>, <b>HF</b>, <b>LF/HF</b>, <b>LF Peak</b>, <b>respiration rate</b> and <b>Coherence Score</b>. Each session also shows <b>artifacts</b> and <b>coverage</b>. Below 5% is excellent, below 15% is good, and 15% or more is invalidated. Each session is compared with a 7-day <b>baseline</b>. Settings can export your data as CSV. <b>Disclaimer</b> Lens HRV is a technical tool for personal data tracking and analysis. It is not a medical device and does not provide medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional for any health-related decisions.

publisher

78ce6faa72264387284e647ba6938995735ec8c7d5c5a65737e55130f026307d

first seen

2026-09-21T21:38:50.410338+00:00

last event

2026-10-08 01:36 UTC

install

zapstore.dev or any Zapstore-compatible client

source & build

repository

https://github.com/lenshrv/lenshrv-app

arch flags

android-arm64-v8a android-armeabi-v7a android-x86 android-x86_64

manifest

missing

releases (kind 30063)

1 release indexed; latest 1.0.2.

assets & verification

Every app, release and asset event is schnorr-verified (NIP-01 id + signature) before it enters the catalog, and assets are content-addressed by sha256. We subscribe read-only to the catalog relay — never write to it.

1.0.2 — LensHRV-v1.0.2-foss.apk

sha256

486b1b3a2a15867e034cbd2b4482565616765bacc6284abe9e5787a87a76bf52

size

2.3 MB

archs

android-arm64-v8a, android-armeabi-v7a, android-x86, android-x86_64

version code

3

apk cert sha256

f6b9ba76d63fb11d584147e330e7f6c6a2bf4e515487b47a6ea51acf05929368

download

LensHRV-v1.0.2-foss.apk

Showing the newest 1 asset descriptor; the full set is in /api/apps/78ce6faa…