How to Sign a PDF on iPhone or Android Without an App
Sign a PDF on your phone in the browser. Draw with your finger, type or upload a signature, place it on the page and save the signed copy.
You can sign a PDF on an iPhone or Android phone without installing anything. Open Sign PDF in Safari or Chrome, choose the document, draw your signature with your finger (or type it, or upload a photo of it), tap the page where it belongs and download the signed file. The document is signed in your browser and never leaves your phone. Sign PDF is available on Pro.
Signing on a small screen has a few quirks, mostly around getting the file onto the phone and producing a signature that actually looks like yours. Here's the whole process, start to finish.
Step 1: Get the PDF onto your phone
Most documents that need signing arrive by email. Before you can open one in a browser tool, save the attachment:
- iPhone: open the attachment, tap the share button and choose Save to Files. Pick a folder you'll remember, such as Downloads.
- Android: tap the download icon on the attachment, and it's saved to your Downloads folder.
If the document is on paper, photograph each page and turn the photos into a PDF with Photo to PDF first. Photos taken sideways are turned upright automatically.
Step 2: Create your signature
Open Sign PDF and choose the file. Then pick one of three ways to create the signature:
- Draw. Sign with your finger or a stylus in the drawing area. Choose black, blue or red ink and adjust the pen width. If an attempt looks shaky, undo it and try again.
- Type. Enter your name and choose one of the handwriting styles. This is the tidiest option on a phone, and it works well for initials too.
- Upload. Use a photo or scan of your real signature. A white or light gray background can be made transparent, so there's no box around the ink on the page.
Finger-drawn signatures look better if you turn the phone sideways for a wider drawing area, sign more slowly than you would on paper, and choose a slightly thicker pen width.
Step 3: Place it on the page
Tap the spot on the page where the signature belongs. It appears there, and you can drag it to fine-tune the position and pull a corner handle to resize it. What you see on screen is where it lands in the downloaded PDF.
If the document needs signing in several places, move to the next page with the page arrows and tap again. You can add the signature to as many pages as you need.
To date the document at the same time, switch on the option that adds the date next to each signature. The date text can be edited, so you can match the format the document expects.
Step 4: Download and send
Apply the signature and download the signed PDF. On an iPhone, Safari saves downloads to the Downloads folder in the Files app unless you've changed that setting; on Android, Chrome saves them to Downloads. From there, attach the signed copy to your reply or upload it wherever it's needed.
Open the downloaded file once before sending it, to confirm the signature landed where you expected and that every page that needed signing has been signed.
Forms with fields to fill in first
If the document also asks for your name, address or ticked boxes, fill those in before signing. When the PDF has interactive fields, Fill PDF Forms detects them so you can type answers and tick boxes on your phone, and it can flatten the answers so they can't be changed later. Then open the completed form in Sign PDF and add your signature.
Is a signature added this way valid?
A drawn, typed or uploaded signature is an electronic signature: a mark that shows your intent to sign. Electronic signatures are widely used for everyday documents such as leases, consent forms and internal approvals, but whether one is acceptable depends on the document, the jurisdiction and what the other party requires.
Some agreements, government filings and regulated processes ask for a certificate-based digital signature or a witnessed signature instead. Sign PDF doesn't create certificate-based signatures. If you're unsure, ask the person who sent the document what they need before you sign.
Privacy on a phone
Signing apps and e-signature services often keep your document and your signature on their servers. With PDFSpark, the document, your signature image and the signed result stay on your phone, because the signing happens inside the browser tab. When you're finished, the only copies that exist are the ones you chose to save.
FAQ
Do I need to install an app to sign a PDF on my phone?
No. Sign PDF runs in mobile browsers such as Safari and Chrome. Open the page, choose the file, sign and download.
Can I sign more than one page?
Yes. Move between pages with the page arrows and tap to place the signature on each page that needs it.
Can I use a photo of my real signature?
Yes. Choose Upload and pick the photo. A white or light gray background can be made transparent so only the ink shows on the page.
Is Sign PDF free?
Sign PDF is available on Pro. See pricing for the plans and what each includes.