We've seen a few Pokemon Go style games of late, not least the most recent AR mobile game based on Ghostbusters, but those with a love for the Catholic church need look no further than Follow JC Go.
It is heavily inspired by Pokemon Go, clearly. However, instead of small, sometimes irritating monsters you have to collect saints and other biblical figures. And rather than capture them in a ball, you have to answer questions about them once found.
You collect the religious figures in an "e-team" - standing for evangelisation.
The game also requires the player to keep his or her avatar nourished by collecting objects scattered around the city. These help your levels of hydration, nutrition and prayer.
And there is in-game currency, but all spending in game is donated to charity.
We're not yet sure which cities work in Follow JC Go. Italian newspaper Corriere Della Sera managed to play the game in Milan, so it is available outside of Vatican City itself.
It is also only available in Spanish at present - perhaps surprisingly considering its origin - but is apparently coming in other languages soon. It is a free download for iOS and Android and we expect it will come to the UK too in time.