Dlink just came out with their new water sensor. I use some of their stand alone ip wifi cameras and really like the interface. The WiFi works on them well and they have an ethernet port. I believe this water sensor is just WiFi, for those that do not have an apex or have another spot in the house they want to watch for water leaks without buying another ald module from apex.
http://us.dlink.com/products/connected-home/wi-fi-water-sensor/
http://us.dlink.com/products/connected-home/wi-fi-water-sensor/