Offline Mass Propers This app is an offline version of the chant tools available at http://bbloomf.github.io/jgabc/ It is mostly intended to be useful for containing the Gregorian Mass propers as well as the Gregorian Mass ordinaries as found in the Liber Usualis, and transcribed on GregoBase (http://gregobase.selapa.net) and there may be some mistakes in the chant. If you notice any, they can be corrected in GregoBase (if you go to http://bbloomf.github.io/jgabc/propers.html and find the chant with the mistake, you can click the link above the chant on the left side to get to the GregoBase version of the chant, and edit it there to fix it, or request that it be fixed.)