OCR (Tesseract) appOCR (Tesseract) is Graphics tool that is open source under the Apache-2.0 license. This app bundles OCR functionality (based on Tesseract) that can be called from other apps via Intents. It listens for Intents with action "org.totschnig.ocr.action.RECOGNIZE" and expects an Uri pointing to a JPEG file as data. The recognized text is passed back in the extra "result" as an object of a parcelable data class Text, that must be copied into the client app.
This app is not intended to be useful stand-alone. It was created out of the motivation to not blow up the size of an application that makes use OCR for a feature that is not needed by all users. Currently it is used by My Expenses for scanning receipts.
Before you start using it, you need to configure the language that Tesseract should use, which triggers the download of the necessary trained models, hence the need for INTERNET permission.