What the Mac app does that the phone can't
The iPhone app can only read a file you hand it. Your Mac already has the conversations on it.
Reads Messages directly
Grants take one click. The app lists every thread on the Mac with its message count and date range — pick one and press Analyze. Nothing to export or find in Finder.
Apple Mail too
Long email correspondences are read the same way as a text thread. The app groups your local mail by the person you were writing to, quoted replies and signatures stripped out.
Or any export you already have
Drag in a WhatsApp, Instagram, Signal, Telegram or Android export — .txt, .csv, .json, .html, .zip or .gz. Files from other machines and other apps work the same.
Two reads, side by side
Every report opens in its own window, so you can put two of them next to each other and compare. On a phone there is only ever one thing on screen.
Mirror Veil, if you want it
Off by default. Switch it on and names, numbers, addresses and card digits are redacted in the copy that leaves your Mac — the analysis still runs on the shape of the conversation.
One account, every device
Sign in and the reads you ran on the web or on your iPhone are already there. A read started anywhere finishes everywhere.
Installing it
The app is signed and notarized by Apple, so it opens normally — no right-click, no security warning to click past.
- Open GreyMirror.dmg and drag Grey Mirror into your Applications folder.
- Launch it and sign in — the same account you use on justlay.me.
- To read Messages, the app asks for Full Disk Access and opens the right pane of System Settings for you. Switch Grey Mirror on and come back.
- Pick a conversation and press Analyze.
Why Full Disk Access? macOS keeps your message history in a protected database. Reading it is the one thing an app cannot do without that permission — it is the same switch Time Machine and backup tools use. Grey Mirror opens the database read-only and never writes to it. You can revoke it at any time in System Settings › Privacy & Security.
Where the analysis runs
Worth being exact about, because it is the thing people assume wrongly.
The conversation is uploaded. Grey Mirror reads the thread on your Mac, then sends it to Grey Mirror's servers, which is where the analysis actually runs. It is not local-only computation. Nothing is deleted on a timer: your uploaded files and reports stay in your account until you delete them, and nothing you send is used to train models. Turning on Mirror Veil redacts names and identifying details before the upload leaves your machine. The full detail is in the privacy and deletion policy.
The download
| Version | 3.4 (build 26) |
| File | GreyMirror.dmg · 8.2 MB |
| Requires | macOS 14 Sonoma or later, Apple silicon |
| Signed by | Terri Weant (KSK8PANM58) · notarized by Apple |
| SHA-256 | 989510b0c61323ce3a15104f9f496121b9fe34f69ffa356445c19508a865fb18 |