On the go or at your house and don’t have access to a scanner? No problem, take at your iPhone open NOTES and scan, it’s that easy. You can now stop worrying about trying to find a scanner, just reach into your pocket and you have one ready to be used.

Scan a document

1. Open a note or create a new note.
2. Tap , then tap Scan Documents.
3. Place your document in view of the camera on your device.
4. If your device is in Auto mode, your document will be automatically scanned. If you need to manually capture a scan, tap  or one of the Volume buttons.
5. Drag the corners to adjust the scan to fit the page, then tap Keep Scan.
6. You can add additional scans to the document or tap Save when you’re done.

Sign a document

1. Tap the document in the note.
2. Tap , then tap Markup.
3. To add your signature, tap , then tap Signature . To manually sign your document, select a tool to use, then sign with your finger or an Apple Pencil with a compatible iPad.
4. Tap Done.

Source: How to scan documents on your iPhone, iPad, or iPod touch using the Notes app