I think I saw one in the App store under RPG. It was an old port of some D&D dungeon crawl. I don’t know how well it works or what, but it had a 4 star rating, meaning that ether 1 person voted 4 stars on it, or 40 people voted 3 stars on it, and in my option and exp, any app that has three or more stars is usually worth it if it is free, however if you have to pay, in my option, it should 4 or 5 stars.