whooing is a paid service. You may not understand that you have to pay more to use your household account book to save money. However, we who manage money should look at the utility of the investment rather than the unconditional cost control. If you can earn 30,000 won by spending 3,000 won, it is not a loss. You can also think of the opportunity cost of free and paid. If it's free, you can think of the opportunity cost of not knowing how your data will be used, advertisements that hinder usability, and anxiety about when the data that adds value will disappear over time.