Every once in a while I'll hear a blind person's phone audio while I'm out and about and it sounds like an unintelligible stream of noises, but they're interact

Every once in a while I'll hear a blind person's phone audio while I'm out and about and it sounds like an unintelligible stream of noises, but they're interacting with it and using it and getting information from it. It's amazing, a whole other world of interaction from what I experience with my phone. I kind of want to learn how they're interacting with it.