Best Free Apps to Sign PDFs on Android in 2026
Free apps to sign pdfs on android does not require expensive software or deep technical knowledge — but it does require knowing which specific actions make the…
"Signing a PDF" covers two different things, and picking the wrong tool for yours is why signatures get rejected. A drawn or typed signature is an image placed on the page — fine for most agreements, and what nearly everyone actually needs. A digital signature is a cryptographic certificate that proves who signed and detects any change afterwards. The apps below are clear about which they do.
Adobe Acrobat Reader
The most reliable free option on Android, and the one to use if the document has a real signature field or came from an Adobe workflow. Handles field-based signing that other apps skip entirely, and supports certificate-based signatures where you already hold a credential. Free for filling and signing.
Xodo
Free, no watermark, no account. Draw a signature, save it for reuse, place it anywhere on the page. Also fills forms and reorders pages, so it covers the whole "return this completed document" job in one place. Places a visible signature; not a certificate-based one.
Google Drive
Already installed, and adequate when someone needs a signed copy back quickly. Open, annotate, add your mark, share. Limited, and the limits are obvious as soon as the document has real form fields.
Dropbox Sign and DocuSign
Different category: signature workflows rather than PDF apps — send a document to several people, track who has signed, keep an audit trail. Free tiers are limited by volume. If you are collecting signatures from others rather than signing yourself, this is the shape of tool you want, and an audit trail is often what makes a signature defensible in practice.
Getting a signature that looks right
Two practical points. Draw it once and save it for reuse — every app above supports this, and a consistent signature looks considerably better than a fresh scrawl each time. And flatten before sending if the recipient must see exactly what you placed: an unflattened signature is an annotation, which some viewers do not render and most printers omit by default.
If you would rather do it on a larger screen, Sign PDF places a drawn, typed or uploaded signature from the browser and exports a flattened copy.
How this list was put together
These are capability comparisons drawn from each tool's own documentation and generally available behaviour, not a hands-on benchmark. Prices and version numbers are deliberately left out: they change often enough that a stale figure here would be worse than none. Check the vendor's page for current pricing before committing to anything paid.
Frequently asked questions
Is a drawn signature on a PDF legally binding? In many jurisdictions an electronic signature can be binding, but it depends on the jurisdiction, the document type and what evidence of intent exists. For anything consequential, ask whoever requires the signature what they accept — and for a definitive answer, a lawyer rather than a PDF guide.
What is the difference between an electronic and a digital signature? An electronic signature is any mark indicating intent, including a drawn one. A digital signature is cryptographic: it binds the signature to a certificate and detects later modification. Digital is stronger; electronic is what most documents actually ask for.
Why does my signature disappear when I send the file? It was an annotation the recipient's viewer does not render. Flatten before sending.
Can I sign a PDF that has a signature field, on Android? Adobe Acrobat Reader is the dependable option. Most other Android apps place a picture next to the field rather than filling it, which some workflows reject.
