Working on an app that mimics a chequing/savings account, where the savings sats are accumulated through mandatory weekly DCA, and the spending sats are calculated by the accrued value in fiat terms of each savings transaction. In theory, there would be weeks where the app allows no spending sats (provided that the savings sats to not accumulate in fiat value)

And just like a regular chequing/saving account the app collects a monthly fee