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 Defense Language Institute - Foreign Language Center:
The Headstart2 Military Phrases app exposes users to 50 mission-specific tasks containing 750 terms and phrases. These tasks include vocabulary covering public safety, medical situations, basic command, cordon and search, and even gathering intelligence. Headstart2 provides users with important communication tools that are needed in preparation for deployment. The material was developed by the Technology Integration Division of the Defense Language Institute Foreign Language Center in Monterey, California.