How to fill out and sign a form on iPhone (PDF forms, done properly)

School enrolment packs, medical intake forms, rental applications, waivers — the defining feature of a form is that the signature is the easy part. It’s the fifteen text fields, six checkboxes, three dates and “initial each page” that turn a two-minute job into an evening. Here’s how to do the whole thing on an iPhone, honestly.

First: is it a “fillable” PDF or a flat one?

Some PDFs have real interactive fields — tap a box, the keyboard opens. If you got one of those, Apple’s built-in tools handle it well: open it in Files or Mail, tap the fields, type. iOS also has AutoFill for forms that can suggest your name and details. If every field lights up when tapped, you may need nothing else but a signature at the end.

Most forms in the wild, though, are flat scans — a photocopied page saved as PDF, where nothing is tappable. That’s where the fiddling starts.

Filling a flat form with Markup (free)

iOS Markup can do it: pencil icon → + → Text for each field, drag it into place, resize, repeat. It works. But be honest with yourself about the experience: every text box is manually placed and sized, checkboxes mean drawing ticks freehand, dates are typed character by character, and a two-page form means doing all of it twenty times. For one short form a year, fine. For anything longer, it’s the digital version of filling the form out twice.

Filling a flat form with Signed

Signed treats form-filling as the core job, not an afterthought:

Import the PDF — from Mail, Files, Photos (yes, a photo of a paper form works) or any app’s share sheet.
Text fields: tap, type, place — your name fills itself in for the fields that want it.
Checkboxes: a proper ✓ element, not a freehand scribble.
Dates: drop in with today’s date pre-filled.
Initials: create them once, then stamp every “initial here” line from your saved library.
Signature last: your saved signature — drawn, typed in a handwriting style, or AI-generated — placed exactly on the line.
Export a flattened PDF and send it wherever it needs to go.

Everything happens on your phone — the form with your kid’s medical details or your salary on it is never uploaded anywhere.

Honest tips whichever tool you use

Zoom in before placing anything. Both Markup and apps place more precisely when the field fills your screen.
Match the ink. Black or dark blue reads as “pen” on any form; novelty colours read as “edited PDF”.
Check page 2. The classic fail is returning a form with the back page blank — scroll the whole document before exporting.
Photograph paper forms in even light. A shadow across the page survives into every copy you send.