A familiar document task gained a dedicated app
iOS 26 brought Preview to iPhone in 2025, giving PDFs and images a dedicated place for viewing and common document actions. The initial feature set included reading, markup, form-related actions, scanning and export. This guide stays within that practical scope rather than attributing every later Preview feature to its first release.
Use a compatible iPhone running iOS 26 or later. Some PDF capabilities depend on the document itself: an interactive form, a flat scan and a restricted signed PDF are not interchangeable. Preview can help with an ordinary form or reference file, but it cannot guarantee that a recipient accepts every kind of electronic signature or edited document.
Begin with the actual file
Open Preview and locate the PDF through its browsing interface, or open the document from Files using the appropriate app option. Check the filename, page count and first page before editing. If several similar downloads exist, choose the correct source rather than the most recent item by habit.
For a form you need to return, make a separate working copy in Files when appropriate. Name it for the purpose, such as Workshop form working.pdf. Keep the untouched original so you can restart if a field is filled incorrectly or the recipient asks for a different treatment. A renamed copy is easier to identify than several files all called form.pdf.
Read the instructions before adding marks
Scroll through the whole document once. Look for required fields, submission instructions and any requirement for an original signature or unmodified attachment. A form may ask for a date as part of its contents; fill it only according to the actual task. Do not confuse the form's requested information with a need to edit the document's underlying wording.
In Preview, open the PDF and tap Form Filling, then tap the field you want to complete. Use AutoFill where offered for supported information, or type the value yourself. The Add control can offer a text box or signature when the document needs one rather than an existing interactive field. Verify every filled field rather than assuming a contact record contains the correct address or name for this particular submission. For a flat PDF, a text annotation may be necessary, but it should not cover the printed label.
Mark up with a clear purpose
Open the Markup controls for annotations such as a short note, highlight, text or signature where supported. Keep marks legible at ordinary viewing size. A signature placed through Markup is an electronic mark; it is not the same as a certificate-based digital signature with cryptographic validation. Follow the recipient's requirements for the document.
| Document task | Useful approach | Check before sending |
|---|---|---|
| Read a reference PDF | Open and navigate the pages | All relevant pages are present |
| Fill supported form fields | Use the form controls and verify values | Text fits and required fields are complete |
| Add a brief explanation | Use a clearly positioned annotation | Original instructions remain readable |
| Sign where electronic marks are accepted | Use the supported signature workflow | Recipient accepts that type of signature |
| Digitize a paper page | Scan and inspect the resulting PDF | Edges, small text and page order are correct |
Work through a workshop form
Suppose a community workshop sends a two-page registration form. Save the original, create a working copy and read both pages. Fill your contact details, choose the relevant session and add a signature only if the instructions allow that method. Zoom in to check that a long email address has not been clipped.
Then zoom back out and read the form as its recipient will. A field can contain the right characters but be placed in the wrong box. Confirm that the second page has not been overlooked and that no annotation obscures the consent wording. Save the completed copy with a name that identifies it as the return version.
Scan only when the source is actually paper
Preview's scanning option can create a PDF from paper documents. Use even light, align the camera and inspect each page before finishing. If the issuer already supplies a clean PDF, printing and rescanning it usually adds work and can reduce legibility. Use the digital original unless the process specifically requires paper handling.
For a multi-page scan, check order and completeness before sending. A readable first page does not establish that the last page was captured. The scanning guide provides a fuller paper-to-file inspection sequence when the scan itself is the main task.
Export and inspect the copy that will leave the phone
Use the available share or export controls to save or send the finished document through the required destination. Open the saved output from Files and verify its name, page count and visible fields. An export is a separate artifact; later edits to the working document may not update a copy already attached to a message.
If the upload rejects the document, inspect the destination's stated size and format requirements. Do not repeatedly add screenshots of each page unless the recipient accepts images instead of a PDF. If a document is locked or signed in a way that prevents editing, request the correct fillable source or submission method rather than trying to strip its protections.
Use the smaller screen for a bounded task
Preview on iPhone is particularly useful for reviewing a short attachment, filling a modest form or returning an annotated page while away from a Mac. For a long packet with many source documents, Mac Preview offers more room to inspect thumbnails and page order. Choose the device that lets you verify the result comfortably.
The 2025 app's value is the completed handoff: the right file, readable changes and a checked return copy. Keeping those steps visible makes a routine PDF task dependable without turning the phone into a miniature desktop publishing system.
Sources & further reading
Apple’s documentation supports the feature details. The scenarios and decision sequences above are CJVV’s editorial guidance.