Water activated MOB device

[roa312]

I have been searching for water-activated man overboard devices - and not the type where the alarm is triggered by the sensor/transmitter getting out of range of the receiver. This is intended for children onboard when in harbor. I would appreciate any suggestions or first-hand experiences from anyone!

I've found the following two systems:

1. ALERT2 Overboard Transmitter: This seems to be close to what I'm looking for, except that it requires an ALERT2 receiver. I would prefer a system that can connect to smartphones or tablets, ideally linking the transmitters to multiple devices. However, if anyone is familiar with this system, I'd be very interested to hear if it can be modified or "hacked" to meet this need.
2. CrewWatcher by PanPan: This product seemed to be exactly what I was looking for, but it appears the company is no longer in business, and I haven't been able to find any stock available online.