An urgent PDF lands while you're away from your desk. You need to add a signature and a page number, send it back, all from your phone.
iOS has Markup built into Files and Mail — useful for signatures and annotations. For real editing, browser-based tools work on Safari without needing an app.
For quick markup, use Files
iOS Files (and Mail) include Markup — Apple's annotation tool. Tap the file, tap the markup icon, draw or sign. Works for signatures, highlights, and quick notes.
No install, no friction. But it's annotation only — no text edits, no page operations, no form fields.
For real editing, use a browser tool
Open Safari and go to Flint's editor. Tap to upload the PDF. The full editor loads on mobile, optimised for touch.
Add text boxes, insert images, merge multiple PDFs, reorder pages, sign. Everything works on mobile, just slower than desktop.
Sign and send back
For signed-back-and-forth workflows, Flint's signing tool handles the whole flow on mobile. Draw the signature with your finger, place it, save, share.
iOS Share Sheet integrates with email, messages, AirDrop. Send the signed PDF without leaving the browser.
FAQ
Why not use the built-in iOS Markup?
Use it for annotations and signatures — it's great for that. For actual editing (text changes, form fields, page operations), use a browser-based editor.
Will the edited PDF save back to Files?
Yes. Download from Safari and save to Files, iCloud Drive, or any connected service.
Is mobile editing slower than desktop?
A bit. Touch is less precise than a mouse, and screens are smaller. For multi-page heavy edits, desktop is faster. For quick changes, mobile is fine.
Can I OCR a scan on iPhone?
iOS Files has limited built-in OCR. For full OCR with searchable PDF output, use Flint's editor in mobile Safari.
Your iPhone is a fully capable PDF editor with the right browser tool. Open Flint in Safari and finish what you needed to finish.