MacJags is a Mac OS X GUI for Bayesian analysis. It is intended to be a Mac replacement for WinBUGS and OpenBUGS and is based on the JAGS library. For more information on using MacJags for Bayesian modeling, refer to the JAGS documentation.
Note that MacJags is in an indefinite state of pre-alpha release. It is not under active development. If you would like a more stable alternative, consider using WinBUGS or OpenBUGS with WineBottler. A tutorial is available on my blog.
License information is available in LICENSE. Note that JAGS itself is released under a separate license from this software.