Information based on AppIndex.com and Wikipedia:
With a C# shared codebase, developers can use Xamarin tools to write native iOS, Android, and Windows apps with native user interfaces and share code across multiple platforms.[4] Xamarin has over 1 million developers in more than 120 countries around the world as of May 2015.[5]
In software development, PhoneGap is a mobile development framework created by Nitobi. Adobe Systems purchased Nitobi in 2011.[3][4] It enables software programmers to build applications for mobile devices using JavaScript, HTML5, and CSS3, instead of relying on platform-specific APIs like those in iOS, Windows Phone, or Android.[5] It enables wrapping up of HTML, CSS, and Javascript code depending upon the platform of the device. It extends the features of HTML and Javascript to work with the device. The resulting applications are hybrid, meaning that they are neither truly native mobile application (because all layout rendering is done via web views instead of the platform’s native UI framework) nor purely web-based (because they are not just web apps, but are packaged as apps for distribution and have access to native device APIs). Mixing native and hybrid code snippets has been possible since version 1.9.
The software underlying PhoneGap is Apache Cordova.[6] The software was previously called just “PhoneGap”, then “Apache Callback”.[7][8] Asopen-source software, Apache Cordova allows non-Adobe wrappers around it, such as Intel XDK or Appery.io.
Appcelerator is a privately held mobile technology company based in Mountain View, California. Its main products are Titanium, an open-source software development kit for cross-platform mobile development, and the Appcelerator Platform, a mobile engagement platform that provides cross-platform native mobile app development using JavaScript, mobile backend as a service (MBaaS), mobile test automation, crash detection and performance management, and mobile analytics.
iFactr provides the only mobile platform that supports both legacy and modern Windows as well as iOS and Android. Whether building new apps or modernizing existing systems, iFactr was designed from the ground-up for mission-critical enterprise line-of-business apps, providing rich, native experiences for every platform and support for critical sensors on rugged devices like barcode scanning and geolocation.
Qt is a cross-platform application development framework for desktop, embedded and mobile. Supported Platforms include Linux, OS X, Windows, VxWorks, QNX, Android, iOS, BlackBerry, Sailfish OS and others.
Based on:
http://appindex.com/blog/ten-best-cross-platform-development-mobile-enterprises/