It's not 30% CPU usage. It wastes one full core because it's currently not using multiple threads. It tries to run as fast as it can, and on single-core machines (yes I'm talking about smartphones here!) this is a pretty common scenario.

I'm also not aware of a way to download the source code. On the bitp.it website there is no button, link etc. to do so. I'm guessing there is a way to download it after you sign up, but nothing anyone could know if there is just a generic "sign up enter email here" field on the site. So it's completely obvious that not everyone reads the code, because it is de facto not open source.