J2ObjC vs. ManifoldJS

J2ObjC is an open-source command-line tool from Google that translates Java code to Objective-C for the iOS (iPhone/iPad) platform. This tool enables Java code to be part of an iOS application's build, as no editing of the generated files is necessary. The goal is to write an app's non-UI code (such as data access, or application logic) in Java, which is then shared by web apps (using GWT), Android apps, and iOS apps.

manifoldJS takes the meta-data about your site and generates native "hosted" apps. If the platform doesn't support hosted apps, we use Cordova to polyfill it. manifoldJS is based on the latest W3C Manifest working draft.