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WHAT A PDF! on your phone

The same tools you use on the web, plus the one thing a browser cannot do: sign a PDF with your digital certificate.

Download for iPhone and iPad Join the Android beta

The Android app is in closed testing. Leave your email and we will add you.

Sign with your digital certificate

This is the reason the app exists. A browser has no safe way to reach the certificate stored on your device, so signing with one has to happen in a native app.

  • Real PAdES signatures, with LTV so the signature stays verifiable years later.
  • Your certificate never leaves the device. It is not uploaded, copied or held by us at any point.
  • Use the certificate you already have installed on the phone.

On the web, our signature tools add a drawn or typed signature and a verification trail. That is enough for most agreements, but it is not a certificate-based signature. For that, use the app.

And everything else you already use

Open a PDF straight from Mail, Files or Photos
Convert, merge, compress and run OCR without a computer
Scan a document with the camera and get a clean PDF
The same account and the same files as the web

Where you can get it

iPhone & iPad

Available on the App Store for iPhone and iPad.

Download for iPhone and iPad

Android

In closed beta. Sign up and you will get an invite as soon as there is a free slot.

Join the Android beta

Questions people ask

Do I need an account?

Only to sync files with the web. The tools themselves work without signing in.

Is it free?

Yes, with the same free allowance as the web. A paid plan lifts the limits and works across both.

Why can the app sign with a certificate and the website cannot?

A web page cannot read the certificate store on your device, and asking you to upload the certificate file would mean handing us your private key. A native app can use the certificate in place, which is the only way to do this safely.

When will Android be out of beta?

There is no date yet. Joining the beta is the fastest way to get it and to hear when it opens up.

Rather stay in the browser?

Most of our tools need nothing installed. Open one and drop your file on it.

WHAT A PDF! for Gmail - Chrome Extension

Open PDF attachments from Gmail directly in WHAT A PDF!. Edit, sign, and convert your PDFs instantly!

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