Privacy
What leaves your Mac, exactly
The app has no account and no login, and sends nothing about you anywhere. Two things can make a network request, both listed here, both switchable in Settings → Privacy.
1. The update check
Once a day the app asks GitHub whether a newer release exists. It sends nothing but the request itself; like any web request, GitHub sees the IP address it came from. Nothing is downloaded or installed. On by default, off in one switch.
2. The anonymous usage report
Off by default. If you opt in, the app posts one small report (about 1 to 2 KB) a day to this site. You can read the exact report in Settings → Privacy before deciding, and the app will mention the choice at most three times, ever: once in the welcome walkthrough, once three days in, and once more only if a monitor is misbehaving. Every field it can contain:
| schema | which version of this field list the report follows |
| reportGroup | a random code, redrawn every 90 days, never derived from hardware; groups one setup's reports so it is counted once, not once per day |
| day | the calendar day the report covers; nothing anywhere is finer than a day |
| appVersion | the app's version, e.g. 1.16.0 |
| os | the macOS version, e.g. 26.5.2 |
| mac | the Mac's model identifier, e.g. MacBookPro18,4 |
| displays[] | per monitor: vendor, model, marketing name, connection (DP, HDMI, internal), how it is controlled, whether it responds, and how many brightness reads failed that day. The serial number is stripped before the report is built. |
| setup | how many displays, which matching mode, whether auto-follow is on, and a few advanced-settings values (wake delay, DDC read attempts) |
| calibration | how many monitors have a dim end set, both ends set, or a weak span, and how far the master can travel |
| counters | daily totals from the app's own log: launches, slider drags, mode changes, auto-follow moves, setup changes, read failures, and the like |
| masterLow / masterHigh | the lowest and highest master position that day, to one decimal |
Never collected
Display serial numbers (stripped before the report is even built), hostname, username, file paths, location, any free text, any timestamp finer than a calendar day, and anything you do on screen. There is no account, so there is nothing to join a report to.
What the server keeps
The report and the calendar day it arrived, one row per setup per day, deleted after 400 days. The server code never reads or stores the address a report came from. Like any web request, the hosting platform (Vercel) sees that address in its own request logs for a short time; that is outside this site’s code and is the same asterisk the update check carries.
Switching the report off throws the grouping code away; opting back in later starts a new one. The honest fine print: a Mac model, a macOS version and an exact set of monitors together describe an unusual setup fairly distinctively. That identifies a configuration, not a person, and nothing links it to one.
This website
Page views are counted with Vercel’s cookieless analytics, served from this origin: no cookies, no third-party request, no profile. Fonts are self-hosted for the same reason.
The reasoning behind all of this is in It sends nothing about you.