Comment by svat

Big fan of the idea of offline in-browser tools: works on any device, and "installing" the program is as simple as visiting a webpage or opening the saved HTML file. This one uses WebAssembly, but even that isn't necessary: I wrote a couple of PDF tools for my own use that simply use pdf-lib: https://shreevatsa.net/pdf-pages/ https://shreevatsa.net/pdf-unspread/