I have found that the most useful tech based tools for foiling is Ikitesurf.com, it's incredible to be able to see the wind speed before you head to the water. When I combine the windspeed with the GPS data in Strava I've learned a lot about the best conditions. I was having so much FUN I foiled all winter in the Gorge. I often go by myself on downwinders so I challenge myself to stay up on the foil as long as possible, I can looking at my speed which tells me how long I was up on the foil. It's also fun to load the data into relive to see my run on a 3D map.