The "Download Now" link directs you to the iTunes App Store, where you must continue the download process. You must have iTunes installed in order to open the link, and you must have an active iTunes account to download the application. This download may not be available in some countries.
From Konrad Group:
Operation Unplugged CheckIn allows you to complete your CheckPointmissions. Its simple to use and will help you add points to yourOperation Unplugged account seamlessly. Rack up points just by beingnear valid CheckPoint locations!Features:Connect with an existing Operation Unplugged account or create a new oneSee available CheckPoint missions at a glanceOne tap check-in when in valid location for selected mission to completeCollect points and earn a badge for completing each CheckPoint missionGo to operationunplugged.com for more detail and information.Note: an Operation Unplugged account is required to use OperationUnplugged CheckIn. To create an Operation Unplugged account, go tooperationunplugged.com or download the app and follow the prompts.