I’ve made a spellbook PWA (progressive web app) for 5th Edition DnD. It’s in alpha. I’ve seeded it with spells from the SRD made by WOTC (hopefully this counts as credit for now, will update later with in app proper credit).
Once installed as a PWA it should in theory run offline.
Main reason for this post is so that I have a link to it here.
Hopefully will have a more proper update soon.