One piece of anecdata: after first getting into Claude Code and then discovered the Claude app I briefly got excited about using it in voice chat mode, demonstrated this to my Austrian wife who found it immediately cool then of course asked if she could chat with it in German. On finding the answer was no, she immediately signed up for ChatGPT so she could use the same feature in her native language. I’m sure Anthropic models are decent with German in text chat, but the lack of that one feature is what drove her straight to a competitor.

German has been supported in Claude voice mode since May.