I'm the developer. I wanted a PDF reader that lets me highlight and take notes without ads, without an account, and without my documents going to someone else's server. I couldn't find one, so I built it.
Source: [Dev.to](https://dev.to/dhruv1206/i-made-reader-a-free-pdf-reader-for-highlighting-and-notes-no-ads-no-account-syncs-through-your-25i0)