From AppleVis: Updated for iOS 27: A Guide to Braille Screen Input on iOS and iPadOS

iOS and iPadOS come with a feature that lets you type in braille right on the touch screen. It’s called Braille Screen Input, or BSI for short. It supports all the same codes and languages that work with supported braille displays. BSI can do several useful things:

You can type braille in your preferred language and code, right on the touch screen

you can search for and open apps from the home screen just by typing part of their name

you can issue commands using braille, just like you would with a braille display connected

you can use letters to move around a webpage, such as typing a braille h to move to the next heading

you can type braille to search for on-screen controls, similar to VoiceOver’s Item Chooser

you can move around and select text you’ve written

you can quickly send messages with a gesture instead of having to find the Send button

Braille Screen Input doesn’t output braille, of course. It’s all on the touch screen, and you still have to use speech or a connected braille display for output. Still, for those who know braille, BSI is a game-changer. Typing can be far faster than with the normal on-screen keyboard, finding and opening apps is very convenient, and command mode lets you navigate your device while staying in BSI. You can even re-assign gestures, such as giving yourself quick access to cut/copy/paste.

Read the full guide