Do you really need an app to sign a PDF on iPhone?
The App Store is full of PDF signing apps, and most guides will tell you to download one. But in 2025, you do not need to install anything. Modern browsers on iPhone — including Safari and Chrome — support the Web APIs needed to read, process, and download PDF files entirely on your device. A well-built web tool can do everything a native app can do, without the storage footprint, the permissions requests, or the subscription fees.
Signvert is one such tool. It runs entirely in your browser, processes your document locally (nothing is uploaded), and lets you sign using your finger, a typed name, or an uploaded image of your signature. The result is a signed PDF you can download directly to your iPhone's Files app.
Step-by-step: Sign a PDF on iPhone in Safari
- Open Safari and go to signvert.com.
- Tap "Upload Document" on the home screen. Your iPhone's file picker will open — you can select a PDF from Files, iCloud Drive, Google Drive, or your Downloads folder.
- Choose your signature method. Tap "Draw" to sign with your finger on the touch canvas, "Type" to generate a stylised text signature, or "Upload" to use a saved image of your handwritten signature.
- Place the signature. Tap anywhere on the document page to position your signature. Drag to reposition, and pinch to resize.
- Tap "Download Signed PDF". Safari will prompt you to save the file. Choose "Save to Files" and select your preferred folder.
The entire process takes under 60 seconds. No account creation, no email verification, no watermark on the output.
Does it work in Chrome on iPhone too?
Yes. Signvert works in both Safari and Chrome on iOS. The experience is identical — the file picker, drawing canvas, and download all function the same way in both browsers. If you prefer Chrome as your default browser, you do not need to switch to Safari for this.
The tool also works on iPad, where the larger screen makes the signature drawing canvas particularly comfortable to use with your finger or an Apple Pencil.
What about Apple's built-in Markup tool?
iPhones have a built-in Markup feature that lets you annotate PDFs in the Files app or Mail. It works well for simple signatures on clean documents. However, it has some limitations: it does not let you type a signature, you cannot upload a pre-saved signature image, and the output is sometimes saved as an annotated image rather than a true PDF with an embedded signature layer.
For most professional use cases — signing a contract, a rental agreement, or an NDA — a dedicated tool like Signvert gives you more control over signature placement, style, and output quality.
Is it safe to sign documents on iPhone using a browser tool?
The key question is whether the tool uploads your file. Many browser-based PDF tools do upload files to a server for processing, which means your document leaves your device. Signvert does not. All processing happens in your browser using JavaScript — your PDF is read from your device's memory, modified, and written back, without any data being transmitted over the internet.
This matters particularly for sensitive documents: employment contracts, tenancy agreements, NDAs, financial documents, and medical forms. With Signvert, you can sign these on your iPhone with confidence that the content never leaves your device.
Frequently asked questions
Can I sign a PDF sent to me by email on my iPhone?
Yes. In the Mail app, tap the PDF attachment to open it, then tap the Share button and choose "Save to Files". Once saved, open Signvert in Safari, tap "Upload Document", and select the PDF from your Files app. After signing, download the signed version and share it back via email.
Does the signed PDF look professional?
Yes. The drawn or typed signature is embedded as a clean image layer on the PDF page. Recipients viewing the document in Adobe Acrobat, Preview, or any PDF viewer will see a professional-looking signature in the correct position.
Is there a file size limit?
There is no enforced file size limit. In practice, very large PDFs (over 50 MB) may take a few seconds to load on older iPhones, but they will process correctly. For most documents — contracts, forms, agreements — file sizes are well under 10 MB and load instantly.