Glossary

Accept-with-flag — allowing a punch that failed the location check, marked for later review. The design that keeps a technical failure from becoming unpaid time.

Accuracy radius — the uncertainty the phone reports alongside a position. Frequently optimistic indoors, and the field that explains a disputed refusal.

Buddy punching — one person clocking in for another. A geofence addresses the version done from home and barely touches the version done on site.

Clock-in radius — the boundary size. The single most consequential setting, and usually left at a default.

False rejection — a punch refused when the worker was present. Costs more than a false acceptance, which is why the radius should lean generous.

Fallback — the route to clocking in when the primary method fails. Its absence is what turns an ordinary failure into a wage claim.

Geofence — a boundary around a site. At building scale it is the same size as the position error, which is the whole difficulty.

Indoor positioning — estimating position without satellites, from masts and visible wifi. Much less accurate, and it is where attendance actually happens.

Mock location — a phone setting or app that reports a false position. Freely available, detectable in the casual case, not preventable.

Punch window — accepting a clock-in within a period either side of the shift start. Removes the shift-change crush at no cost.

Refusal rate — refused punches as a proportion of attempts, per site. The headline operational measure, and most deployments do not track it.

Terms used loosely by vendors

"Tamper-proof" describes nothing achievable. Mock location tools exist and work.

"Proof of attendance" means a device registered a punch inside a boundary. It does not establish who was holding it.

"Real-time tracking" in an attendance product means background collection, which the clock-in function does not require.

"Face verification" covers both a photograph a human glances at and a biometric match against a template. The second carries a much higher legal bar.

"Compliance" describes a deployment, never a product.

How to read these notes

Start with the technical section if you are deciding whether this can work at your sites — the accuracy note comes first.

Start with the basics if you are deciding whether to buy at all.

Start with the legal section if you operate in Europe, where consultation and prior authorisation may both apply.

Start with common failures if a deployment is generating complaints.

Nothing here is legal advice, and the notes say so where it matters.

On the absence of numbers

How to treat any figure here.

No accuracy figures beyond broad ranges, because they depend on the phone, the building and the time of day.

No savings percentages, because vendor figures are best cases.

No prices, which vary by size and negotiation.

Every number worth having is your own, measured at your own sites, and the notes say how.

Turn the principle into a test

For an example that can make this requirement testable, consult this practical example. Treat the page as a starting point rather than proof and reproduce the workflow with real roles and failures.