Our youngest (15m) has recently started sleeping through the night on her own, without us needing to get up for feeding or settling. But she's still waking (one of) us up, because she often cries a bit before falling back asleep. Turning the monitor off entirely is an option, but then if something were pretty wrong (ex: vomiting) we might keep sleeping. I'd be interested in a monitor with a configurable delay: only turn on the monitor if they've been crying for, say, 8min.

A monitor like this would also be useful for sleep training. One common approach is to pick some sort of timing pattern for when to go back in to settle the baby, and not go back in before then. For example, you might settle them, and then hope they stop crying and fall asleep, but if they're still crying in 15min you repeat. Trying to ignore someone you're very attached to cry while trying to remember when exactly it will have been 15min while super sleepy is not fun. If baby monitors had configurable snooze buttons, after settling the baby you could snooze the monitor and try to fall back asleep. If you're lucky they fall back asleep before the fifteen minutes are up, and you more sleep.

There are a bunch of ways to make this fancier, including only counting crying and not other noises or identifying unusual crying, but even something basic like turning on when the average recent volume reaches a threshold would be very helpful.

I did find someone who built a prototype using a phone, with a much shorter delay (10s). I can't find any products, though. Would other people find this useful?