These are the two best mission types available, and choosing between them is mostly about which failure mode you would rather live with.

How each one works

Scan mission: you register a specific QR code or barcode. The alarm stops only when the camera reads that exact code. Matching is exact, so it either passes or it does not.

Photo mission: you photograph a place in your home during setup, such as the bathroom sink. The alarm stops when you take a similar-enough photo of the same place. Matching is by image comparison, so there is a judgement call involved.

Side by side

Scan missions and photo missions compared.
 Scan a codePhoto of a place
SetupRegister a code, about a minutePhotograph a spot, seconds
MatchingExact, pass or failApproximate image comparison
Speed at 6amFast once framedUsually fast, fussier in the dark
Works in poor lightNeeds enough light to read the codeImage matching struggles more
Can the target disappear?Yes, products run outRarely, a sink stays put
Easy to cheat?Only with a saved photo of the codeEasier, a photo of the place works
Anchored toAn objectA place
AppsMornio, Alarmy, SuperAlarm, Nuj, Alarm ScanAlarmy

Where the scan wins

Where the photo mission wins

Which should you choose?

If you want speed, certainty and a follow-up check, take the scan. If you keep forgetting to re-register when the toothpaste runs out, take the photo mission. Alarmy is the app to use for photo missions; it also supports scanning, which makes it the natural choice if you want to try both.

The compromise many people land on: a printed QR code. It combines the exactness of a scan with the permanence of a photo target, because you choose where it lives and it never runs out. Tape or laminate it if it is going in a bathroom.

The thing that matters more than either

Where you put the target. A perfect mission aimed at your nightstand does nothing, and a mission in the garage gets abandoned within a fortnight. One room away is the balance that survives winter, and it beats any decision about mission type.