With the rapid growth of iOS, Android and Windows platforms in the last few years, the responsibility of the App developer to adapt their Apps to different platforms has increased.
Are you a Developer using Windows 7 and want to develop iPad and iPhone Apps ?
Rhomobile is a HTML5 application development platform and supports Windows Embedded Handheld, Windows Phone, Apple iOS, Android and BlackBerry.
3. Sencha Touch
Sencha Touch is a HTML5 Mobile App Framework which allows the Mobile App developers to develop apps that has the native look and feel of Apple iOS and Google Android platforms.
JQuery is a touch optimized version of one of the popular jQuery framework targeting the Mobile platforms. JQuery currently supports iOS, Android, Windows Phone and more platforms.
Titanium from Appcelerator is a free and open source framework to develop apps using Web technologies.
Cross Mobs is a Software Development Kit (SDK) where the developers can develop iOS and Android games using C++.