This is really nice - the simplicity of the interface and ability to read papers without sacrificing the readability of math equations is awesome. Congrats on publishing it. Do you mind sharing how you convert from pdf to html (if at all)? I'm building a tool for reading, curating, and visualizing personal knowledge [1]. Apps like yours and others mentioned in this thread are nice ways to discover papers and address blind spots during literature reviews.
[1] https://www.knowledgegarden.io