React Native ML Kit — Text Recognition (OCR)

@nitro-mlkit/text-recognition · on-device Google ML Kit via Nitro Modules — JSI, no bridge.

⚠️ Beta (0.1.0-beta.x). Android is verified on-device. iOS builds and links (GoogleMLKit via CocoaPods) but on-device runtime validation is still pending — see Platform status. API may change before 0.1.0.

High-performance, on-device text recognition (OCR) for React Native, built with Nitro Modules — JSI, synchronous crossing, no bridge and no JSON serialization.

Powered by Google ML Kit's bundled Latin text-recognition model. Returns the full recognized text plus a structured block → line → element hierarchy with bounding boxes. All on-device — nothing leaves the phone.

Installation

npm install @nitro-mlkit/text-recognition@beta react-native-nitro-modules

Ships native code, so it does not run in Expo Go — use a development build or the bare workflow. No config plugin: it's an Expo module, autolinked automatically. Just install and prebuild:

npx expo prebuild

Usage

import { NitroText } from "@nitro-mlkit/text-recognition";

// Just the text (convenience)
const text = await NitroText.recognizeText(imageUri);
// → "Hello Nitro MLKit"

// Full structured result (blocks -> lines -> elements + bounding boxes)
const result = await NitroText.recognize(imageUri);
// result.text                       -> the whole string
// result.blocks[i].lines[j].text    -> a single line
// result.blocks[i].lines[j].elements[k].bounds -> a word's box

// Native batch — ONE JSI call, N images recognized concurrently
const results = await NitroText.recognizeBatch(galleryUris, 4 /* concurrency */);
// → [{ index, text, success, error? }]

NitroText.isAvailable(); // boolean

API

| Method | Status | | ----------------------------------- | ------ | | recognize(uri) | ✅ structured | | recognizeText(uri) | ✅ flat string | | recognizeBatch(uris, concurrency) | ✅ native concurrency | | isAvailable() | ✅ |

Currently ships the Latin script model. Chinese / Devanagari / Japanese / Korean are separate ML Kit models and are a possible future addition.

Platform status

| Platform | Min version | Status | | ------------ | ----------- | ----------------------------------------------------------------------------------------- | | Android | API 21+ | ✅ Verified on-device (Pixel 9 emulator, API 36): recognize → correct text (1 block/line) in ~190 ms; recognizeBatch 20 imgs in one call (~730 ms) | | iOS | 15.5+ | ⚠️ Swift impl written; on-device build & run pending¹ | | tvOS / macOS | — | 🔜 Planned |

¹ Google ML Kit's iOS pods ship no arm64 Simulator slice, so iOS must be validated on a physical device.

Part of nitro-mlkit

The full ML Kit suite on Nitro. See also @nitro-mlkit/face-detection, @nitro-mlkit/image-labeling and @nitro-mlkit/barcode-scanning.

License

MIT © Gonzalo Polo