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.
This is the iPhone version of the open-source Task Coach desktop application (http://www.taskcoach.org/). It features basic task editing and synchronization with its desktop counterpart over the network.If you plan on using this feature, please take a look at the "iPhone" section in the documentation of the Task Coach desktop application (version 0.73.2 at least).