Google Play Store won't let me install the application
On none of my devices. The only common criteria I can think of is that I am in France. That's also what suggest the fact that I don't get the same result with https://play.google.com/store/apps/details?id=chat.fluffy.fluffychat&gl=US and https://play.google.com/store/apps/details?id=chat.fluffy.fluffychat&gl=FR.