How we know this

Where the data comes from

The source of everything here is the Rosetta Check macOS app. It scans a Mac locally — reading application metadata and Mach-O binary headers to determine which installed software is Intel-only, Universal, or native Apple Silicon. Scanning is entirely on-device.

Users can then opt in to Community Sharing, which contributes an anonymous summary of their Intel-only apps to this catalogue. Sharing is off by default and requires a deliberate action; the full list of what a contribution does and does not contain is on the About & Privacy page. 6,873 Macs have contributed so far, and data arrives continuously — the most recent scan was processed on 24 August 2026.

What counts as evidence

A device reporting an app is a sighting: that Mac, on that date, had that Intel binary installed. Each app page shows the count of distinct devices reporting the app, when it was first reported, and when it was most recently seen. Duplicate counting is prevented with a random per-device identifier, so one Mac scanning daily still counts once.

Version histories work the same way — the versions listed for an app are versions real devices actually reported, not a vendor changelog.

How "gone native" claims are verified

When we say a native Apple Silicon build of an app has been spotted, that claim has a specific meaning: a Mac in the community ran the app's binary through the same Mach-O architecture check and explicitly reported a native or Universal build, with its version and CPU architecture. These are labelled confirmed sightings — there are 708,491 of them — and only devices that have previously contributed scans can report one.

Separately, when an app quietly disappears from a device's Intel list, we record a weaker inferred signal — the user may have updated to a native build, or may simply have deleted the app. The two are never mixed: pages and prose use softer language ("may have been updated") when the evidence is only inferred.

The bar a page must meet

We deliberately do not treat every reported binary as worth publishing. An app page is only offered to search engines when at least two independent Macs have reported the app and enough context exists to write something useful about it. Apple's own bundled software is excluded — it ships with macOS and needs no migration page.

Single-device reports stay in the catalogue and remain reachable — early evidence is still evidence — but they are held back from search indexes until a second device confirms them. Of 29,089 tracked Intel apps, 13,324 currently meet that bar.

Freshness

This dataset maintains itself: the installed base of Macs re-scans and re-contributes continuously, so every app carries a live "last reported" date rather than a publication date. When the community stops seeing an app, that is visible too — an app whose last sighting is years old tells you something a vendor page never will.

Where AI is used — and where it isn't

The telemetry — device counts, dates, versions, sightings — is never AI-generated. It is measured. AI (Anthropic's Claude) is used to write the prose descriptions and migration recommendations on app pages, and each one is generated from that app's own measured data plus current web evidence, then refreshed on a rolling cycle so it does not go stale. AI-generated content is labelled as such wherever it appears.

Community-submitted alternative suggestions are reviewed by a human before they get a verification checkmark.

Honest limitations

• Contribution is opt-in, so device counts are a lower bound — an app seen on a dozen Macs here is installed on far more in the wild.
• The contributing population skews toward people who care about the Apple Silicon transition; it is not a random sample of all Mac users.
• Version strings are whatever vendors ship in their apps' metadata, which is occasionally messy.
• A confirmed native sighting means a native build exists and runs — it is not a statement about how that build is distributed. Where the route to it is unusual (beta channels, opt-ins), the page's guidance says so.