Review on 🚴 Waterproof Bike Computer Wireless - GPS Speedometer for Road Bicycles with Bluetooth and ANT+, Ideal for Cycling Computers by Billy Braggs

Does not cost money. It's not very accurate, it's not very easy to set up. If you go where there are many trees, then it spoils with precision. I'll probably just toss it in a drawer and eventually throw it away. I'm not sure I'll even keep it as a backup. I'm sticking with my wireless cateye. It's much more accurate than GPS. For this information I simply use my Garmin HR watch.