Kotoba - Voice Translation
Predictive AI Live Translation
Only for iPhone
Free · In‑App Purchases
iPhone
"Kotoba" is a real-time voice simultaneous translation app developed by Kotoba Technologies, aiming to deliver the "world's best simultaneous translation experience."
The app is powered by Kotoba's proprietary speech GenAI model called "Koto".
"Koto" can predict text translations before you finish speaking (up to 0.5 seconds ahead) or generate coherent speech translations with ultra-low latency.
■ Features
・Ultra-low-latency speech-to-text and speech-to-speech translation (preview) — translations appear before you finish speaking
・Real-time translation from the moment you speak (live subtitles)
・All you need is your smartphone—no need to hire expensive human interpreters or carry bulky dedicated translation devices
・Translation results can be shared and saved as text instantly
・Multilingual support (see "Supported Languages" below)
■ How to Use
1) Open the app
2) Press the microphone button and speak
3) Translations appear on screen in real time
4) Connect your headset or earbuds via the headset button for speech-to-speech translation
■ Perfect for These Scenarios
・Don't want to miss what others say in online or in-person meetings
・Frustrated with the wait times and usability of conventional translation apps
・Want to have richer conversations with locals while traveling or on business trips abroad
・Want smoother customer service and reception for international visitors
■ Media & Events
Featured on NHK, TV Tokyo, Forbes Japan, Abema TV News, and more.
■ Supported Languages
・English ⇔ Japanese
・English ⇔ Chinese
・Japanese ⇔ Chinese
・Japanese ⇔ Korean
■ Plans
The Unlimited Plan (monthly/yearly) removes the 5-minute session limit and the 1-hour monthly usage limit.
*Latency, accuracy, and predictive display may vary depending on network conditions, device performance, and ambient noise.
Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Experience the moment when language barriers disappear—download now.
© 2026 Kotoba Technologies Inc.
Bug fixes and performance improvements.
The developer, (株)Kotoba Technologies Japan, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Contact Info
- User Content
- Identifiers
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- KOTOBA TECHNOLOGIES, INC.
- Size
- 38.3 MB
- Category
- Reference
- Compatibility
Requires iOS 17.6 or later.
- iPhone
Requires iOS 17.6 or later. - Apple Vision
Requires visionOS 1.3 or later.
- Languages
English and 4 more
- English, Japanese, Korean, Simplified Chinese, Traditional Chinese
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Unlimited Monthly $99.99
- Unlimited Plan $999.99
- Copyright
- © 2025 Kotoba Technologies, Inc.