When you made calculation invoice or product price, you can easily calculate price according to include or exclude tax. Also, you can calculate interest amount according to rate, period, calculation period.
Tax calculate has %1, %8, %18 default values. If you need to other percent, you can enter whatever you want.
The calculation need to rate, period and calculation period in interest calculation. You can enter values according to daily, monthly or yearly.
When using this application, you dont need to internet connection.