You may not even need a third-party app, as your phone likely has a scanner built-in:
: Open Google Drive , tap the "+" button or camera icon, and select "Scan" to create a PDF directly in your cloud storage.
: Widely considered the best free option, it automatically captures and cleans up documents, converting them into high-quality PDFs with OCR (text recognition).
: Known for its strong focus on privacy and simple, fast multi-page scanning.