A Cordova plugin bridges a bit of functionality between the WebView and the native platform the Cordova application is running on.
Plugins are composed of a single JavaScript interface used across all platforms, and native implementations following platform-specific Plugin interfaces that the JavaScript will call into.
Cordova JavaScript Bridge plugin enables the possibility to bridge functionality between the WebView and the native platform using JavaScript instead of native language (eg. ObjectiveC or Java). Such plugin relies upon Javascript Engine available on target OS.
Currently we support only IOS version 7 and above because, from that release, Apple has made available the JavaScript Core framework, an embedded JavaScript engine, outside of the WebView boundaries.
Support for Android has been planned in the next months