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From Christian Stahl:
Allows an easy and fast calculation of value added tax (VAT), rebate and cash discount. Universal application for iPhone, iPad and iPod touch. Manage standard conditions in different projects for faster access, e. g. different tax, rebate and cash discount percentages. Changing one value will calculate the other values automatically. Calculation from net to gross and vice versa by one tap with the same values. Tax, rebate and cash discount are mentioned in percent and as amount, the rebate can be entered as amount and the percentage will be calculated. Send your calculation as Text or Excel (2003-XML) attachment. I am happy to receive a good rating as well as questions or feedback. The application has been tested intesively. If you nevertheless find errors, please report the feedback by Email to my below mentioned address. Please note that error-reports in ratings are not send to the developer. Only with a direct email I can react quickly to solve the error and send an update.