You need to check the bill, figure the tip, and round off the total so that you can split the expenses fairly.

This is a PalmPilot moment, a chance to whip out your organizer and show how it can make your life easier. What software should you use?

What makes a good tip calculator?
It turns out that several different pieces of software are available to help with this little chore. We're going to look at all of them, and see how they stack up. But first, let's consider what makes a good tip calculator.

Calculating tips is not rocket science. You've been doing it for years in your head. There are many little tricks to help out. In my area, where the sales tax rate is a whopping 8.25%, you can figure a 15% tip simply by doubling the tax amount and rounding off. So, any good tip calculator will have to be really fast and really simple if it's going to improve on these rules of thumb. In practice, this boils down to letting you enter just a few numbers and stylus taps, and filling the rest in by itself.

The tip should be based on the total of food and drink before taxes. So, the tip calculator should compute tax and tip separately, but sum them for you.

Tips can and should differ according to the service you received. So, the tip calculator should make it easy to adjust the tip level up and down.

When paying cash, it's often easier to round the total up or down to a convenient amount. The tip calculator should make that easy, and show you how the tip rate changed with the rounding off.

The PalmPilot organizer lets you set your preferences for number formats. A German user may want to see their totals as DM 123,45, while a Canadian would prefer $123.45. A good tip calculator should reflect your preferred formats and currency. It should also be available in your preferred language.

When you dine with friends, you might want to split the bill between you. A tip calculator can help with this task. A really good one could help you figure out how much more or less specific diners should pay, depending on what they ordered.

How we chose the software
For this survey, we picked the tip calculation software readily available on the Internet. We went to a popular PalmPilot software sites, PilotGear H.Q. at http://www.pilotgear.com/, and searched for all software that mentioned "tip". We included the most recent version of each application in this survey. We didn't find any commercially-distributed tip calculators (though one of these is on a commercial CD-ROM).