Wanikani app that is used entirely to help recall and write Kanji. Requires Wanikani API key.App to help you learn how to write Kanji. You are provided a canvas to write Kanji on (although I prefer pen and paper). When you are ready you can reveal the words and be shown how to write it.
The source code can be found here: https://github.com/Munksey
NOTE: This is not an officially endorsed app by wanikani.
Also note, the SVG files are apart of a project called KanjiVG, which can be found here: http://kanjivg.tagaini.net/.