I reached the stage at which Rikaikyun appears to be fully usable (though I haven’t made a lot of tests), so I decided to release it to public (not that it was hidden from public before). You can grab the APK and source code from here. Note the APK will probably not work on anything less than Android 4.
You can also test the app in Chrome using the device emulation mode (you have to run Chrome with the –allow-file-access-from-files flag on). For running the app in chrome there is also a special Chrome hack option that allows emulating pressing back button by going back in browsers history.