So 18 Birdies is an app you can download to help you play golf. It can give you bird's eye view of greens and info on those greens. My question is though, how is this not cheating?
For the most part, courses give you distances on all the holes, where the pin is located, and what the hole layout is. But it can't give you a good backswing and follow through.
The pros can't use that stuff or GPS but like Bengal said they have yardage books that have distances to everything on the course from everywhere on the course.