1. Straighten first if needed
If pages are slightly tilted, run Deskew first. It fixes small tilts of up to about 5 degrees, and straight lines are read more reliably.
2. Run OCR PDF
Choose the language of the document: English, French or Arabic. Recognition runs on your device, so large files take a while on older phones.
3. Search the result
Open the new PDF and search for a word you can see. The page looks the same; the text is now behind it.
Questions
Will the page look different after OCR?
No. The text layer is invisible. The scan looks exactly as before.
Can I get just the text?
Yes. OCR PDF can also export the recognised text as a .txt file.
Related: Scan paper documents with your phone · Convert a PDF to an editable Word file · Convert PDF tables to Excel