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iPhone development tools that work the way you do 
7/29/2009
When Apple opened up the iPhone to developers, O'Reilly books noticed a big jump in sales of its long-neglected titles on Cocoa and Objective C. These elegant dialects never caught on outside of Apple, but when the iPhone SDK appeared, the world started studying up again. If you want to work in Rome, learn Latin. That requirement is starting to fade, though, as new toolkits and development platforms make it possible for programmers to avoid studying Objective C to create iPhone applications. The frameworks take code written in languages like good, old-fashioned JavaScript or newfangled Ruby and give the user complete control of the screen, just like a native application. It still makes sense to learn Objective C if you're programming a fast-moving 3-D game or something that wants to squeeze every ounce of performance from the battery-powered wonder, but everyone else can avoid returning to school now. http://www.infoworld.com/sites/all/themes/ifw/images/promos/deepdive_pro...) no-repeat scroll center top; position: relative; float: right; width: 336px; height: 178px; margin-bottom: 0pt; margin-top: 20px;"> The toolkits also offer a promise of cross-device development, a process that is both surprisingly efficient and a source of endless little disappointments. In theory, your software will run on an iPhone, a BlackBerry, an Android handset, and in some cases even a Symbian phone or a Java ME phone. In practice, the fonts are never exactly the same and little glitches appear from time to time. If you write your code with big strokes, the pictures will look the same, but anyone who frets over the details will find plenty of struggle. I took four of these toolkits -- Rhomobile Rhodes, Nitobi PhoneGap, Appcelerator Titanium, and Ansca Corona -- out for a spin, wrote some code, and came away certain that it was easy to create menu-driven mechanisms for browsing data using any of them. If you want to give the user a nicely tuned interface for a database, it's pretty simple to whip together an application in no time. [ If you are unable to view the table and screen images in this article, please click here. ] Rhodes, PhoneGap, Titanium, and Corona are all good tools. Although there are differences in capabilities, your choice will probably rest with the one that supports your favorite language. That's the entire point of working with these frameworks. If you know JavaScript, Lua, or Ruby, you can create something on the iPhone very quickly. Rhomobile Rhodes If you love Ruby or have Ruby code to port, then Rhomobile's Rhodes framework is a good path for bringing your code to mobile platforms. Rhomobile bundles a byte code version of your code with a tiny Ruby interpreter (version 1.9) to produce "native applications." Rhodes supports all of the major platforms, including iPhone, BlackBerry, Windows Mobile, Symbian, and Android, although I only looked at the iPhone result. It's probably not worth arguing whether a byte code interpreter is truly a native application; that debate is best left to computer science theoreticians. They're certainly more native than Web applications running on the local browser. They usually behave with as much snap as a truly native package, so practical people don't need to worry much about this argument.  
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