Foliato: Offline PDF Tools

Estanislao R. Pérez Nartallo

About this app

Your PDF never leaves your device. Foliato is a complete set of offline PDF tools (merge, split, sign and more) that runs locally on your phone or tablet. No document is ever uploaded to a server.

VIEW YOUR PDFs
Foliato works as a PDF viewer and reader: continuous scroll, pinch-to-zoom, selectable text, pages fitted to your screen width, and it registers as your phone's default app to open PDF files from Mail, Files or Drive.

DIGITAL SIGNATURES: READ AND CREATE
Inspect the digital signatures a PDF carries: who signed it, with which certificate, whether the document changed after signing, whether the certificate chain holds together and, if you leave it on in Settings, whether the issuing authority has revoked the signer's certificate. For that check only the certificate's serial number is sent, never the document. The app always tells you what it checked and what it did not: a certificate not being listed as revoked does not mean it can be trusted. The Information sheet shows size, dates, author, PDF version and whether the document is protected.

SIGN PDF WITH A DIGITAL CERTIFICATE
Sign a PDF with your own digital certificate (.p12 or .pfx, for example from the Spanish FNMT): a real cryptographic signature in the standard PAdES format, with an optional visible stamp on one, several or all pages. When online, the signature includes a timestamp and the certificate is first checked for revocation; offline, it still signs. You can save your certificates encrypted on the device, but the password is never saved: it is asked for on every signature. It is an advanced electronic signature, not a qualified one.

10 PDF TOOLS, NO UPLOADS
• Merge PDF: combine several PDF files into one document
• Split PDF: extract just the pages you need
• Reorder: drag pages into a new order
• Rotate: fix a sideways or upside-down page
• Compress: shrink the PDF's size with an adjustable compression level
• Sign PDF: draw your signature once and place it on any page
• Sign with certificate: sign with your digital certificate
• Image to PDF: turn photos or JPGs into a PDF, one page per image
• Watermark: add a text watermark, then drag, resize, rotate and fade it
• Page numbers: pick the format, position and starting number

OFFLINE AND PRIVATE
Every tool works offline: no account, no ads, no analytics. Your files stay on your device from open to export. Only two features look things up online, and only when you use them: signing with a certificate (timestamp and revocation check) and the revocation check when you open a signature, which you can turn off in Settings. Neither ever sends your document or your full certificate.

FREE, NO CATCH
All 10 tools are unlimited from the first launch. No in-app purchases, no subscriptions, and Foliato never adds its own watermark to your files.

Foliato is available in English, Spanish and French, with light and dark mode.

What’s new

Foliato 1.3.0 introduces Sign with certificate: sign a PDF with your own digital certificate (.p12 or .pfx, for example from the Spanish FNMT) in PAdES format, with a timestamp and a revocation check when online. Save your certificates encrypted; the password is never saved. The signature inspector now also checks whether the signer's certificate has been revoked, sending only its serial number.