It allows you to enter your own training sequence and save it to localstorage.
I created this because I have a weird keyboard (Kinesis Advantage2), and none of the training apps I saw online helped me train with the keys I really needed to train with (parens, curly braces, control-key combos, etc). Maybe I just didn't look hard enough, but I figured how hard could it be. Thus this was born.
You will want to run a simple http server to serve the files. That is all that is required. Here are a few:
https://www.npmjs.com/package/http-server
https://github.com/cesanta/mongoose
https://docs.python.org/2/library/simplehttpserver.html
This update requires a new method of adding control keys like arrows, tabs, etc. They should not be in their own arrays anymore, but just treated like any other string sequence. However they must be separated by the interpunct: "·".