The download area is at :
http://agora.lal.in2p3.fr/download
Here can be found various binary kits but also some example data files.
agora is available on the AppStore since January 2012.
agora is available on the Android Market for devices with at least Android-2.0. Note that the agora-release.apk is also available from the download area.
On a Mac, download and unzip the agora.app.zip, then click on the agora icon (or do : open agora.app, from a terminal). Remember that data files are searched within the directory :
~/Documents/agora