Waiter15% is one of the easiest to use tip calculators out there. There are no gimmicks or fancy user interfaces...just simplicity and functionality.
Selling points:
1. No advertising whatsoever.
2. No advertising whatsoever (à la "Fight Club").
3. It is FREE until
- downloads go viral.
- new features are added in future releases.
- the developer needs the money.
4. Tip amount is properly calculated using the subtotal amount (i.e. pre-tax amount).
5. Default 15% tip percentage can be used or a custom tip percentage can be entered.
6. Tip amount can be entered and the tip percentage is then calculated.
7. Sales tax % is automatically calculated or a custom sales tax % can be entered.
8. Round total per person or total amount by directly editing the textfields.
9. "Subtotal $$" and "Subtotal %" buttons can be used to calculate the subtotal by backing out the sales tax.
Example 1: Receipt total (including $8.25 sales tax) is $108.25 but no subtotal is given. Enter $108.25 as subtotal and enter $8.25 as sales tax amount. Press the "Subtotal $$" button to back out the sales tax amount from the receipt total. Subtotal ($100) = total ($108.25) - sales tax ($8.25).
Example 2: Receipt total (including 8.25% sales tax) is $108.25 but no subtotal is given. Enter $108.25 as subtotal and 8.25% as sales tax %. Press the "Subtotal %" button to back out the sales tax amount (in %) from the receipt total. Subtotal ($100) = total ($108.25) / 1.0825.
