The download button opens the iTunes App Store, where you
may continue the download process. You must have iTunes installed with an
active iTunes account in order to download and install the software. This
download may not be available in some countries.
From Joseph Slinker:
Longshot is the simplest way to enjoy a round of Disc Golf with your friends. The clean interface gets out of your way and lets you focus on the game. Record scores and track progress for multiple players on multiple courses.