# OpenKoto — 用喜欢的内容学语言

> 用喜欢的内容学语言 (iPhone/iPad app by 倍铭 刘.)

- Source: https://appshunter.io/ios/app/openkoto/id6793335573 (this page in markdown: same URL + `.md`)
- Developer: [倍铭 刘](https://appshunter.io/developer/1831757727)
- Category: Education, Utilities
- Price: Free
- Age rating: 4+
- Requires: iOS 18.0 · 9 MB
- Languages: American English
- Released: 2026-08-01
- Data updated: 2026-09-07
- User reviews in markdown: https://appshunter.io/ios/app/openkoto/id6793335573/reviews.md

## What is OpenKoto?

OpenKoto is an open-source, privacy-first language-learning app. Turn the articles, books, and videos you genuinely care about into study material, understand sentences in context, collect vocabulary, and review it on a schedule.

Key features:

• Paste text or import TXT, Markdown, and web content
• Import TXT and EPUB books with automatic chapter splitting, in either a sentence-by-sentence view or the book's original layout
• Import video and audio with SRT / VTT subtitles — or generate subtitles on device when you have none (requires iOS 26)
• Subtitles follow playback sentence by sentence; tap a line to jump to it, loop a single sentence, change speed without changing pitch, and hide the text to shadow by ear
• Read sentence by sentence, resume where you left off, and add bookmarks and highlights
• Show word-level readings above Japanese and Chinese text (furigana / pinyin), generated entirely on device
• Search the full text of everything you have imported — articles, book chapters, and media transcripts — and jump straight to the sentence
• Save vocabulary, organize word packs, and use spaced-repetition review; jump from any card back to the sentence it came from
• View reading and review statistics
• Use the app in English, Simplified Chinese, or Japanese
• Choose light, dark, and multiple visual themes
• Send web pages or selected text to OpenKoto from the iOS share sheet

Optional AI features use a bring-your-own-key model. Configure a compatible provider of your choice for translations and sentence explanations. API keys are stored in the iOS Keychain, while learning content and progress stay on your device. AI requests go directly from your device to your selected provider and do not pass through an OpenKoto app server.

No account is required. Sample articles are included, so reading, vocabulary, and review features work without configuring an AI provider.

OpenKoto is free and open source.


## Version history (last 4 releases)

### 0.6.1 — 2026-08-26

• Word lookups are now saved — no need to look up the same word again after restarting
• New 3-step import wizard: choose a type, add your content, confirm and done
• New guide for downloading and importing videos with subtitles

### 0.6.0 — 2026-08-14

• AI web cleanup can remove navigation, ads, recommendations, comments, and footer noise while preserving the original article; switch back to the original at any time
• AI explanations now render Markdown with clearer headings, lists, and emphasis
• Media subtitles now support original, bilingual, and translation-only display modes, with more reliable subtitle following and translation dialogs
• Refined vocabulary, review, and library interfaces, plus multiple stability fixes

### 0.5.5 — 2026-08-06

• Improved compatibility with reasoning models including GPT‑5, the o-series, and Gemini 2.5 by adapting output-limit and temperature parameters automatically
• Automatically retries once after temporary rate limits or dropped network connections, making batch explanations and translations more reliable
• Batch jobs now retain the failure count and specific cause, retry only recoverable items, and no longer hide errors such as insufficient balance or authorization failures
• Copy a redacted diagnostic report after an AI request fails to help identify provider, model, network, or configuration issues; API keys are never included

### 0.3.0 — 2026-08-01

No release notes.

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-07.*