EyesRhythm is an offline, no-account desktop app that scores your blink rhythm on-device

A new desktop application called EyesRhythm has appeared on Hacker News as a Show HN launch, promising to help desk workers keep healthier blinking habits — and to do so without sending a single frame of video off the user's computer.

What the app does

According to the EyesRhythm website, the app uses a laptop's built-in webcam or a USB camera to detect each blink and measure how frequently blinks happen. Beyond raw counting, it also scores how evenly those blinks are spaced, on the reasoning that the same number of blinks can mean very different minutes depending on whether they arrive in a tight burst followed by a long dry stretch. The two measures are combined into a single "Ocular Rhythm Index" scored from 0 to 100, shown beside a live graph covering the last five minutes of blinking.

The app only counts while the user is actually at the screen. When it intervenes, it aims for gentle rather than intrusive: a soft orange visual pulse is the default alert, with an optional sound mode and an optional beep on every counted blink for a tighter feedback loop. A "Practice" mode runs a two-minute guided session intended to pace blinks until the habit becomes easier to feel.

Poise tracks the neck's half of the problem

EyesRhythm also watches which way the head turns. The site describes a "Poise" dial divided into 30-degree slices that turns green in directions the user looked and stays red in directions they skipped. The reasoning is that long computer sessions park the neck in a single position, and a prompt to rotate up, down, left and right gives the neck and shoulders a chance to ease before returning to the screen. The developer is careful to frame this as a reminder, not a treatment.

The privacy posture

The most technically interesting part of the launch is what the app refuses to do. The EyesRhythm site states that camera frames are read locally and then discarded, that no video is uploaded or retained as a recording of the face, and that daily totals and settings are stored in a local folder. There is no account, no license key, no cloud backend and no analytics. The app is free; version 1.6.0 ships as a roughly 93 MB disk image for macOS and an 85 MB installer for Windows, and the developer says it has been tested on Intel Core i7 machines and on Mac processors.

Background and caveats

The developer says the project grew out of personal experience: more than two decades as a software developer, with long screen hours that gradually produced dryness, redness and discomfort in the eyes. The site claims that focused computer use often cuts blink rate roughly in half, and that sparse, uneven blinking is a known contributor to digital eye strain, dryness and fatigue. Those points align with common advice about screen work, but here they are presented by the product's maker rather than verified independently. The site is also explicit that EyesRhythm is a wellness companion, not a medical device, and that lasting discomfort or changes in vision should go to an eye-care professional.

Why it matters

Camera-based wellness tools usually carry an implicit cost: to get insights about your face, you generally have to hand over a live video feed and trust wherever it is processed. EyesRhythm is a small but clean example of the opposite pattern — perception happens on the device, nothing leaves it, and the absence of accounts, license keys and analytics means there is no server-side footprint to breach, misuse or lose. The health claims deserve the usual skepticism since they come from the product's own marketing, and the long-term usefulness of a blink coach is an open question. But as an architectural statement — webcam input, on-device processing, zero telemetry, zero login friction — it is exactly the privacy-first pattern worth watching in a category where cloud processing has quietly become the default.