Here’s what I came across while browsing the finance section of the App Store on my new iPhone:
iTip, from palaware
iTip, from Uncouth Software
BigTipper, from PureBlend Software
TipCalc, from BAMsoft
Tiptap, from Made with Bananas
Tipulator, from tap tap tap
Tip Calc, from Charles Ying
Tip, from Carlos Perez
CheckPlease, from Catamount Software
Tips, from Kudit.com
mTip, from Pascal Mermoz
TipBuddy, from Justin Jeffress
Gratuity, from TapeShow
QuickTip, from Spare Change Software
Tippety Split, from Manta Ray Software
Out of 59 apps in the finance section, at least 15 of them help you calculate a restaurant tip. Some of them also help split a bill between diners and so on; some are free, others cost a dollar. I only glanced at a few of the apps but I can’t imagine there’s a huge difference among them. Which leads me to ask:
1. Is there such a weak demand for real estate in the iPhone App Store that it can afford to give 25 percent of its space to nearly duplicate products?
2. Is it really so hard — even while including certain variables — to calculate a tip?
3. I am all in favor of financial literacy, but isn’t the mastery of restaurant tipping too narrow a skill to demand such attention?
4. I understand that Apple has run into a bit of a buzzsaw with its $1,000 “I Am Rich” app, along with news of an iPhone kill switch, but neither of those cases involved junking up the new sleek worldvibe the iPhone has created — whereas this tip-calc overkill kind of does, no?
Now if someone wrote an app for tipping the flight attendant, I might consider it.
[ADDENDUM: To you long-tail commenters below, who write that "As a virtual store, Apple’s shelf space is essentially infinite," and "There is no physical 'space' limit in the App Store," let me respectfully disagree, at least a bit. Even when real estate is not physical, there are limitations. For instance, let's say I'm willing to browse the first 10 or 20 apps in the finance section -- and see that a bunch of them are tip calculators. Doesn't that make me a lot less likely to wade through the next 30 or 40 apps that might not be tip calculators? Here's a better argument in favor of the reality of virtual real estate: When a post on this blog is linked to from The Times's home page, traffic on that post spikes perhaps five- or ten-fold. But there's only room for so many home-page links -- which means that the vast majority of articles and blog posts on NYTimes.com never appear there, and therefore get read far, far less widely than those that do. Also, ask publishers how hard they work -- and how much money they are willing to pay -- to be featured on an Amazon.com front page of some sort. The tail may be long but fat beats skinny any day of the week.]

I always see those tip-calculators – my cell phone has one. I don’t think I’ve ever seen anyone use them, and if I did, I’d mock the person without feeling bad in the slightest! If you don’t know basic math you’ve got a big problem!
I’m not against tipping (15% for standardly competent service) but since it seems to be required now, rather than an option for particularly good service, don’t see its current purpose.
More restaurants should just fire on a service charge and be done with it.
Do these apps give you the before tax tip of after tax tip or both?
I’ve found when dining w/ a group it’s just easier if one person pays the entire bill and let someone else pay it the next time the group is out. Yes, I know, some may be screwed but look at how much time is being wasted figuring a tip for a number of people
@Travis Ormsby, jonathan
There is a space restriction in the App Store, albeit not a physical one. It’s a complexity restriction – the restriction is on the number of items people can process when making decisions.
People faced with a choice between two items can make the choice. People faced with 15 will walk away confused and not buy any of them.
People don’t want to sift through a mountain of chaff in order to find a quality application.
Microsoft have dicovered this with their console’s online store. It launched with 200 items, it now has 17000, and growth is geometric. They’ve had to plan a full interface redesign as well as serious quality control on the existing and new applications.
Apple should do the same thing.
maybe a waitress wrote the code for the apps
Just a week ago my wife and I were out to dinner. I spent a good 10 minutes explaining how to calculate a 15 or 20% tip. She’s a mathphobe.
The answer to #2 is a resounding Yes!
Tipping is quite simple once you realize that 10% is figured out by moving the decimal in the total one space to the left. It’s basic math.
A $76.59 total yields a 10% of $7.659. If you want to tip 20%, just multiply that by 2.
And if you don’t know the exact math (for $15.32), just round it so that you have $7.70 times 2 for $15.40. And if you’re even worse at math, round to $8 and multiply by 2.
Any worse and you should just tip the amount of the bill because no matter how bad they were, they’re better than your math skills.