Qt vs Codename One
When comparing Qt vs Codename One, the Slant community recommends Qt for most people. In the question“What are the best systems to deliver native Android and iOS apps from one code?” Qt is ranked 3rd while Codename One is ranked 8th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Open-source
Pro Global community
The community behind Qt is both massive and approachable. Digia (also owners) are joined by the likes of Intel, KDAB, ICS, Canonical and numerous others in sponsoring development, while communities such as KDE also contribute significantly. Forums are active, mailing lists are open, irc channels chatting, git repositories well managed. Answers to questions are usually minutes away.
Pro Good documentation
Professional, thorough documentation with examples, available either in a web browser or in the stand-alone desktop client called assistant.
Pro High performance
Pro Open source
Pro Highly customizable
By utilizing lightweight component architecture and the built in graphical designer and theming options you are able to customize a good looking app on any platform.
Pro Java 8 support
Pro Works with all IDEs
Works with NetBeans, Eclipse, IntelliJ, etc.
Pro Multi-platform development environments (via build server)
You can even use Linux desktops to build native iOS apps, no need for a Mac.
Pro Vibrant & helpful community
Pro Attractive pricing
It is possible to build production grade apps even with the free version. Pricing is decent when compared to competitors like Xamarin.