On a personal note, I have been using the original prototype at home, over the last 12 months has reduced my water consumption by around 30%. This was in fact a surprise to me. The financial saving well and truly pays for the unit in the first 3-6 months. It takes a little while to change your behavior but it does happen. The only downside is I find myself cursing the unit on these cold days when a nice long hot shower is welcomed. A number of times I have suspected the unit is not reporting correctly. I did NOT use that much water. I have got a bucket out and measured the flow only to find it is accurate.
As far as I can tell there are no equivalent products. As the display is in the shower and gives immediately in your face feedback. This makes it more effective. There are water meter products around that you then either have to go outside to read or browse with your smart device, these can be easily ignored and overlooked. Aquatrak is there to see when you finish in the shower and there for the next person to see how much you used. It is simple but effective and it works.