To start with the good, I'm pretty happy with the Chrome version. It's a new-style packaged app which was easy to create, 99% of the code was unchanged, the only unsupported feature of the web version was localStorage which needed changing to Chrome storage, which took a bit of code restructuring but works in a similar way.
As a packaged app it works offline by default, and launches in a standalone window, which looks more app-like than a hosted app. I developed the game to work with touch so I expect this version works nicely on the Chromebook Pixel, but I haven't had a chance to try it yet.
Less successful was the port to Android via Phonegap. It took a long time to get this working, I hit some resizing bugs that I had to edit the Cordova source code to get around. I managed to get performance on my Nexus 4 reasonable by stripping out some effects but it's far too laggy on most other devices to call it a success. I can't say for sure that I optimized the game as much as possible, but I wouldn't attempt making an Android game with Phonegap again - at least not one that requires a good frame rate to play well.
So my dreams of developing fully cross-platforms with HTML5 have been slightly tarnished, but I'll be interested to look into other solutions for porting across platforms.
