The race officer's view: who is not yet out, still out and back, marking people by hand, locking a phone, and resetting.
Tallying, in the event's admin, is the board the race officer watches: three columns, Not yet out, Still out and Returned, split by fleet, each with its count.
Lock this phone fixes the device to one job (assigning bands, out, in, or safety) behind a 4 to 8 digit PIN, so it can be left wherever it is needed. For a phone that truly cannot be wandered off, also turn on Android's screen pinning before handing it over.
Reset tallying sends everyone back to Not yet out, for a second day or a second session. Nothing is erased: every tally stays in the activity log, and bands and sign-ins are kept.
Reset all tags clears every band from every entrant, and everyone will need tagging again. It cannot be undone.
Before anybody goes home, the board must read zero still out, and a person must have checked that with their own eyes, not only on the screen.