You're waiting for coffee and the PDF that needs a tiny tweak is sitting in your inbox. The iPhone can mark it up, but actually editing the text — that's where iOS quietly hands you off to the App Store.
You don't need an app. Flint runs in Safari, on the phone in your hand.
What iOS does well — and where it stops
iOS has had Markup forever. You can scribble on a PDF, sign it badly with your finger, and email it back. That's genuinely useful for forms. But the moment you need to change existing text — a date, an address, a typo your boss spotted — Markup stops dead. It draws *over* the page; it doesn't touch the text underneath.
That's the gap Flint's PDF editor fills on iPhone. Open Safari, drop the file in, edit the actual text, save the result back to Files or share it straight on.
The five-step iPhone flow
Save the PDF from Mail or Messages to Files (or just keep it in iCloud). Open Safari and head to flintpdf.com. Tap the editor, pick the file from Files, and the PDF renders inside the page.
Tap any text to edit it inline. Add a new text box if you need to fill a blank field. When you're done, the Download button drops the edited PDF straight back into your Files app — or AirDrop it to your Mac in two taps.
Signing on the same trip
Most iPhone PDF jobs are sign-and-send. If that's all you need, skip the editor and go straight to sign a PDF — draw with your finger, drop the signature on the page, done. If you need to edit then sign (fix a name, then countersign), do both in one Flint session without bouncing between apps.
When to compress before sharing
iPhone PDFs from scans or screenshots are often huge — 30 MB for ten pages isn't unusual. Before emailing or uploading to a portal, run it through compress PDF. A 30 MB scan typically lands around 3 MB without visible quality loss, and Gmail's 25 MB attachment limit stops being a problem.
FAQ
Can I edit a PDF on iPhone without an app?
Yes. Open Safari, go to flintpdf.com, and use the in-browser editor. It works on iOS 15 and later, handles text, signatures, and page changes, and saves back to your Files app. No App Store install, no account required for a quick edit.
Why can't I edit text in Apple's Markup tool?
Markup is designed for annotation — it draws on top of the PDF, not into it. To change the underlying text content (a date, a name, a price), you need a real editor. Flint reads the PDF's text layer and lets you edit it directly.
Is it safe to edit a PDF in the browser?
Flint processes files in your browser session and doesn't store them after you're done. Nothing leaves your phone except what you choose to download or share. It's safer than emailing a PDF to a random online editor.
Does this work on older iPhones?
Anything running iOS 15 or later works smoothly. Older iPhones (8, X, 11) handle Flint fine — the heavy lifting is browser-based, so as long as Safari is up to date, the phone's age barely matters.
Editing a PDF on iPhone shouldn't mean installing yet another app. Open Safari, edit your PDF, download the result. Done before your coffee's ready.