Hi Michal,
Since you're building a native application, does the OCR need to work offline? That would be a challenge.
If an online solution is acceptable, here are some mainstream cloud-based OCR services you can consider:
AWS Textract: https://docs.aws.amazon.com/textract/latest/dg/what-is.html
Google Cloud Vision: https://cloud.google.com/vision/docs/ocr
Microsoft Azure Computer Vision: https://learn.microsoft.com/en-us/azure/ai-services/computer-vision/overview-ocr