Those of you who’ve been paying attention to the apps that came out of iPhoneDevCamp (or who are using Applists, AppMarks, or any of the other iPhone web app aggregators/launchers) are probably already aware, but we just launched our first micro-application named “Tipr” last week.
Tipr is a super-simple web-based tip calculator aimed at mobile devices. You simply enter the bill total and choose a percentage to tip and Tipr does the rest, giving you the tip amount and the total. As an added benefit, the total is always converted to a palindrome to make it easy to spot fraudulent adjustment of your tip amount or total when scanning your credit card or bank statement.
Tipr started off as a tool for me, really. I have been doing the palindrome thing for over a year now and, even with the calculator on my phone, it takes a minute or so for me to calculate out the tip amount to end up with a palindrome for a total. To speed things up a bit for myself, I built Tipr and it’s proven quite useful. I hope you will find it useful too.
We’re trying to keep Tipr pretty simple, but if you have recommendations for improving it, let us know by leaving a comment.
Comments
I really like Tipr, particularly the palindrome feature. Could you describe the math you used to force the result to be a palindrome? The easiest approach that came to my mind is to compute the accurate tip, observe the digits on the left-hand side, then copy those digits to the right-hand side in reverse order.
That’s pretty much what it does, but it also makes sure to round up because, on smaller checks (like $10), it was pretty substantially reducing the tip by just reversing the numbers. Now it tests to see if the palindromic tip amount is less than the original tip amount would be and rounds up if it needs to (so you’re tipping just slightly in excess of your intended tip amount).
I’ve thought about opening up the Tipr calculator as a web service to other applications, but I haven’t found a compelling reason to yet…maybe one day.
Cool! Two UI improvement ideas:
<ol><li>For the Check field, don’t use the normal iPhone keyboard. Create a purely-javascript numeric keypad with big-ass buttons that are easy to type that populates a text area. No need to use the normal keyboard when all you need is 0-9 and a decimal point</li>
<li>And for the percentages, don’t have a pull down but instead simply have 10 buttons, one for each percentage (in fact, nobody tips more than 30%, or for that matter less than 10%, so five or six buttons should be fine). With this, you can then just drop the submit button entirely and simply initiate the calculation with the tap on the appropriate percentage button.</li></ol>
The palindrome thing is great. My wife will love that!
Thanks for the suggestions Chris. I may look into some options like that, but I’ll need to add them in as unobtrusive a way as possible. I am also trying to remain extremely conscious of download times and the fact that over 1/3 of our users are using the non-AJAX version of Tipr, meaning their JavaScript support may be spotty, non-existent, or turned off.
On the subject of the tip percentage though, I do know some people who do tip upwards of 30% on special occasions or who do tip less than 10% when warranted. I wanted to keep it flexible, but start with a sensible default. As a side-note, the SMS interface (via Twitter) allows for fully-customized tip amounts.