I actually had an idea for this. What if blind users could wear little braille terminals? Like, braile is constructed of a series of dots, so why not have like a bracer that has a array of dots that poke the skin?
it might work, but the nerves found in the fingertips are far more sensitive than anywhere else on the body. This might be trainable though, I don't know
The tongue is incredibly sensitive, I've seen some work on giving blind people the ability to have low-resolution vision by having an array of electrodes on the tongue (before the tongue, they used the back, but that's not anywhere near as sensitive) and a webcam.