Take photos and turn them into manga-style.
Chrome Packaged App with videoCapture permission can query user media without a warning. It is also possible to process the image captured by a video camera using WebGL. You can then save the pictures you take to the the sync file system. The pictures will be synced among your devices.
See the source code at https://github.com/GoogleChrome/chrome-app-samples/tree/master/manga-cam