The Catholic App was spearheaded by the Diocese of Edinburgh and St Andrew's in conjunction with Scottish tech firm Musemantik.
It's thought to be the world's first interactive, GPS-powered app to help people find their nearest available place to celebrate Mass or celebrate Confession.
Archbishop Leo Cushley unveiled the app in Rome holding A3 print-outs of iPhones with the Catholic App installed on them, alongside the Vatican's Secretariat for Communication, Fr Dario Viganò.
Before the launch Archbishop Cushley was leading a pilgrimage to mark the conclusion of the Catholic Church's Jubilee Year of Mercy, which happened on Sunday.
