Damn right it'd be useful. I already have a program that uses credits as a currency. If a user could automatically refill said currency, the program I have would work just like it did before, only automatic.

A manual payment option.
A recurring payment option.
Multiple subscription options for different features.

All I need left is the recurring credits. This ie actually what I was hoping credits would be at first actually... useful for a more descriptive "Subscribe" feature. Heck, the program even checks for date expiration, leap years, and has no limits. :)

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