Some, such as Rhodes, allow developers to create native apps for almost all mobile platforms, including the iPhone, Windows Mobile, BlackBerry, Symbian and Android. Similar to PhoneGap, you will have to compile the code for each platform separately. It also supports the native features of most smartphones, including geolocation, contacts, and camera image capture. Rhodes is free under the MIT License. A cloud computing service called RhoHub enables developers to develop applications online using the Rhodes framework, with no need for them to have the latest SDK for each platform on their computer. Apps are created using HTML and Ruby, and are actually built in the cloud.
Will Web Apps Eventually Become the Standard?The World Wide Web Consortium (W3C) recently returned to work on the HTML 5 specification after years of absence. Their return has produced tensions with the Web Hypertext Application Working Group (WHATWG), a group of browser makers (including Opera Software, Mozilla, and Apple) who began work on the standard in June 2004. Ian Hickson, who is the editor of the HTML5 specification, expects the specification to reach the Candidate Recommendation stage during 2012, but doesn't expect it to become an official W3C Recommendation until the year 2022 or later--that's right, over 12 years from now. And now for the good news...
All the major mobile platforms, including Apple's iOS, Google's Android and Palm's WebOS, use similar WebKit-based browsers, so technologies like HTML5 and CSS 3 will continue to be improved and supported. Even Microsoft is coming to the plate with support for HTML 5 forthcoming in MSIE 9. Though it may not become an official standard for a decade, it is increasingly being supported by the major browser vendors, and more sites and services, such as YouTube Mobile, Google Gmail, Scribd, and Apple's iPhone and iPad are using HTML 5 instead of plugins such as Adobe's Flash. HTML 5 is here to stay.
There will always be businesses who feel that they must have a native mobile application for each major platform, however many are starting to be more inclined to work smarter, not harder. The emerging web standards can be used to create compelling applications, as demos from Apple, Google and Sencha show. In the future, a web application should work for the majority of mobile platforms, if not all of them, and it should work on any HTML 5-compliant web browser, whether that browser is on a mobile device or a desktop PC.