Pre-set Sales Tax
You have the ability to enter in a pre-set sales tax percentage inside of the Settings tab. This will allow tax to automatically be calculated and added at the time of sale.
Inventory can be entered with an associated price and quantity under the Items tab. Those items can then be selected and tracked during the sales process.
You can enable a tip prompt at the time of the sale under Settings. This will prompt the customer with custom tip percentages based off of the amount of the sale.