I've had an idea 💡

'Kitty app'

When you go to a bar someone always gets caught with a round of drinks, so some groups add money to a pot to make it fairer, called a kitty

Traditionally the kitty is cash

How about an app on everyone's phone where there is a group function, where each participant adds money to the digital pot

When it's your turn to pay for the drinks at the bar, the total in the kitty is reduced and updates

Could work for fiat

Or in the future on Ln

What do you think?