The tip is a percentage (typically 10-20%) of the bill. You can EASILY select the percentage for tips.
If you dont want to deal with a loose chance to pay more you can calculate by only a single tap.
How does it work?
Enter the bill amount, then increase or decrease the number of people to split the bill between.
If you want to leave a tip, you can decide what percentage of the tip you want, with just a single tap.
If you dont want to leave a tip, then you can just select 0% and then set many people to split between.
The total bill will show by clicking on the Calculate button, along with the share each person has to pay and a number of people.