Via Hog Bay Software:
Outlines are powerful, but can be confusing. In Bike outline editing is fluid, your ideas flow across the screen instead of jumping from position to position. This makes it easier to track what’s going on, and it’s fun!
It's a neat, simple-looking app with a lot of possibilities. As someone who tends to knock out quick, rudimentary outlines in a tool like Drafts, I'd much rather have something like this instead.
It's $29.99 with a free demo available now on Hog Bay Software's website. And be sure to watch the intro video as well.