This app was mentioned in 10 comments, with an average of 1.30 upvotes
UnNetHack on Android is always there for me when I'm queued.
I find the text-based glyphs more and quickly intelligible in Dwarf Fortress than any tileset. I'm using Alloy's square version of the default (makes it easier to judge distance vertically and horizontally). Check out /r/DwarfFortress, it's hopping!
~~Pretty sure unnethack runs both, though I personally have an~~Looks like it currently only runs on android
Apparently there is desire for this to be ported to iOS, though, no idea if there is any progress on that.
Ironically enough, looks like you can connect to a telnet server running it, though, I'm also not sure how that measures up to the actual app