Quick background: I play tennis [a very little bit], and the thing that always bugged me is you finish a match with a feeling but no information. The good rally, the footwork that fell apart in the third set, all gone. Pros have analysts. The rest of us have memory. So my co-founder and I built Wingball. You record your session the normal way and upload the clip to our webapp. It tracks every shot, cuts an auto highlight reel, and gives you a court heatmap plus stats like distance covered, to...