Why scanning matters
A Thread mesh is alive: routers promote and demote themselves, devices sleep and wake, links strengthen and fade. A scan reads the current state — Matter diagnostics from your devices, border-router advertisements, reachability — and every grade and map in the app is built from that evidence. Old evidence means old answers, so if something looks wrong, scan first. It resolves most oddities.
The freshness colors on the Overview
The “Matter & Thread scan captured” row under the health scores tells you the age of the evidence, in color: green — captured in the last 5 minutes; amber — 5–10 minutes old; red (pulsing) — more than 10 minutes old, worth a rescan. The whole row is a button: tap it any time to scan again.
When scans run on their own
With “Diagnostics scan on launch” enabled (the default), Threadlytics scans when it starts and runs a quiet quick-scan when you return to the app after it has been in the background with stale evidence. You never have to remember to scan — but the row above tells you when it would help.
“The scan finished but things are still filling in”
That's real, and it's honest: after the device reads finish, Threadlytics still correlates what it learned — matching identities across ecosystems, updating transports, rebuilding maps. The pill at the top of the screen (“Scanning devices…”, then “Syncing devices…”) shows exactly this work. When the pill is gone, the picture is settled. On a first launch with a large home, give it a minute — the first snapshot is the most work the app will ever do.
What a scan does not do
Scans are read-only. Threadlytics never changes your devices, your mesh, or your ecosystems — it only asks them questions. Scanning as often as you like is safe.
Still stuck? Contact support with your app version (Settings › About).