Wikimedia's Catlin says that Rhodes is good at some things such as synchronizing data to a phone. But he is more a proponent of HTML 5. "The difference is that Rhodes launches a Web server on your phone," he says, while with WebKit, a static Web site is loaded.
"Overall, what's happening in the market is the adoption of Web technologies on mobile phones," says Purnima Kochikar, vice president of the Forum Nokia Developer Community at Nokia. That lets developers' Web skills translate to mobile phones, she says. Plus, "moving from one application platform to another becomes simpler," though she notes that almost all phones require testing of the resulting apps.
But the Web app approach does introduce the issue of not taking advantage of specific platform capabilities. Thus, most platforms let developers do it either way. Developers can build Web apps that run on the iPhone, or use Apple's tools to build iPhone-native apps, for example. Also, RIM offers a Java development environment for building BlackBerry applications as well as a Web development option for building browser-based programs. The Web apps can leverage widget programs created in the BlackBerry SDK. These widgets are essentially Web applications that have access to native applications in the device, creating a bridge between the generic Web app and the target device. Of course, such widgets run only on the BlackBerry. Apple's iPhone SDK has a similar capability that lets developers use both Web apps and native libraries together.
The forthcoming LiMo mobile Linux platform's development environment will use the Bondi widget specification (developed by a consortium of carriers called the Open Mobile Terminal Platform) to allow the creation of Web-based applications that provide a consistent set of capabilities and user experience across specific LiMo devices, notes Andrew Shikiar, the LiMo Foundation's marketing director. Some custom porting may be needed, he notes.
Eclipse tries to deliver a unified mobile app dev platform -- for some devices
The Eclipse Foundation's Pulsar initiative is looking to provide a semblance of unified development for mobile apps, focused on building for Java MIDP handsets but still requiring individual SDKs. So-called feature phones -- the pre-iPhone type of device that comprises the majority of cell phones sold today, such as those from LG and Samsung, and offer less multimedia and application functionality than smartphones -- are the primary target for Pulsar. It's meant to help developers "target most of the [feature phones] running MIDP in the market today," says Motorola's Kurzke.
Pulsar provides an Eclipse-based development environment that accesses appropriate SDKs for developers to build handsets from multiple vendors. Currently supported devices are Android using Motorola's SDK, Nokia S60 series using Nokia's C++ SDK, and BlackBerry using RIM's Java framework. Eclipse hopes to add backing for Symbian phones next year.
Break.com's Taylor, however, was not optimistic about prospects for the project to provide unified development for multiple platforms, given differences in screen resolutions, capabilities, and operating systems.