Built on Claude

How Omut uses Claude

Omut is a native messaging app for iPhone, iPad and Mac that brings Telegram, WhatsApp and Omut into one app. Claude has two roles: the Claude API powers a feature that ships in the app today, and the product itself is built with Claude Code.

32 beta users · 17 weekly active · Live Claude API traffic · Public TestFlight since August 2026 · Built in Tokyo by one founder

Here is exactly how Omut uses Claude, with current product and engineering metrics.

Live today: voice summaries

Long voice messages in Omut chats get a Summary button. The summary is written by Claude Haiku 5.5 through the Claude API, in the reader’s language.

Shipped in TestFlight build 19 on October 7, 2026.

On-device transcriptionClaude APIHaiku 5.5 summaryPer-message cache

  • Speech is transcribed on the device. Claude receives the transcript text, never the audio.
  • Runs only for long messages: over 60 seconds or 600 characters of transcript.
  • Cached per message and language. Parallel requests for the same message share one API call.
  • Every API call is logged with input and output token counts, so we can track cost per user as usage grows.

Production implementationabout 1,450 lines of Rust with tests and 380 lines of Swift

Built with Claude Code

77%

of commits co-authored by Claude: 1,986 of 2,584 in the current native app codebase, started on August 13, 2026.

Omut is built by one founder with Claude Code.

iOS / macOS (Swift)
1,367 of 1,733
Backend (Rust, Postgres)
591 of 819
Website
28 of 32

Roadmap on Claude

Live today

  • Voice summaries in Omut chats.

In development, no promised dates

  • Translation both ways in casual chats.
  • Digests of busy group chats.
  • Chat to calendar: “Friday at 7?” becomes an event.

Planned architecture: Haiku for high-volume workloads, Sonnet where higher quality matters, with prompt caching for repeated per-chat context.

Regional availability

Claude-powered features are available only in Anthropic-supported regions. If the region of a request is unknown, the feature stays off.

Privacy

Nothing is sent to Anthropic unless someone taps Summary. Claude receives the transcript text, never the audio. The summary is cached for that message and language and deleted together with the voice message.

Privacy Policy · Security

Try it

Omut is in a free public TestFlight beta for iPhone, iPad and Mac.

Join the beta

About Omut · [email protected]

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