The language the room speaks
In the meeting's Settings, the first choice is what is actually spoken from the stage. A recent Mac can caption speech in English, Spanish, French, German, Italian, Portuguese, Japanese, Korean or Chinese; older Macs and Windows laptops caption English. Attendees read in any of 100 languages either way, because the translation is made from the caption text.
That difference matters when you plan the rooms. If a session is delivered in Japanese, put a recent Mac in that room. If every room is English, any laptop will do.
The languages people read in
Underneath, you turn on the reading languages for the meeting: 100 to choose from, up to 24 in any one meeting. The list folds into regions with the most used ones open, there is a search, and a running count tells you how many of your 24 you have used.
Which ones? Look at your registration list, and add the ones your delegates actually gave you. Turning on a language nobody reads costs nothing at all, but it does make the choice sheet longer for everyone, so ten is plenty for most meetings.
What an attendee sees
They scan the sign and land on the room. Frasiey asks which language to read in, as a single tap on the first screen, with their phone's own language already highlighted. It remembers the answer, so it only asks once. A meeting with one language skips the question and goes straight to the captions. The language is always one tap away after that, from the small control at the bottom of the screen.
Languages that read right to left are laid out right to left. Anyone who would rather listen than read can turn on Read aloud and their own phone speaks the captions, if you have allowed it in Settings.
Teach it your words
Names, acronyms, product names and the local spelling of a venue are what a room gets wrong, in every language at once. Put them in the meeting's Glossary, one per line, with the spelling you want on screen. It is the cheapest accuracy you will ever buy, and ten minutes the week before is enough.
What to do next
If some of your audience is joining from home, set up Show captions in Zoom or Teams too.