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PDF Tools5 min read · May 12, 2026

How to Sign a PDF on Your Phone – iPhone & Android

Got a contract or form to sign but you're on your phone? Here are three free methods to sign any PDF on iPhone or Android, no Adobe subscription, no printing, no computer required.

Quick Answer

You can sign a PDF on any phone in under 60 seconds, for free, without installing an app. Open Safari (iPhone) or Chrome (Android), go to imageandpdf.com/pdf/sign-pdf, upload the PDF, draw your signature with your finger, drag it to position, and download. iPhone users can also use the built-in Markup tool: open the PDF attachment in Mail → tap the pen icon → sign → Done → share the signed file.

Method 1: Browser tool (iPhone & Android)

Best for: any PDF on any phone. No app needed.

This method works on both iPhone and Android. The entire process happens in your browser, your PDF is never sent to a cloud server.

  1. 1

    Open imageandpdf.com in your browser

    On iPhone, use Safari. On Android, use Chrome. Navigate to imageandpdf.com and open the Sign PDF tool.

  2. 2

    Upload your PDF

    Tap the upload area. On iPhone, you can pick from Files or iCloud Drive. On Android, pick from Downloads, Google Drive, or internal storage. If the PDF arrived as an email attachment, save it to Files/Downloads first.

  3. 3

    Choose your signature type

    Three options: (1) Draw, use your finger to sign on a touch canvas. (2) Type, enter your name and choose a signature font. (3) Upload, photograph your handwritten signature and upload it as an image.

  4. 4

    Drag the signature to position

    After creating your signature, tap and drag it to the correct position on the document page. Resize as needed by pinching.

  5. 5

    Download the signed PDF

    Tap Download. The signed PDF saves to your iPhone's Downloads folder (Files app) or your Android Downloads folder. Email or share it directly from there.

Method 2: iPhone Markup (built-in, no internet)

Best for: quick signatures when you're offline. iPhone only.

iPhone has a built-in signature tool in the Markup feature, accessible from Files and Mail. No internet connection required.

  1. 1

    Open the PDF in Files or Mail

    Open the Files app and navigate to the PDF. Tap to open it. Alternatively, open the PDF from an email attachment.

  2. 2

    Tap the Markup icon

    Tap the pen/pencil icon (Markup) in the top right corner of the PDF view. If it's not visible, tap the screen once to show the toolbar.

  3. 3

    Tap the + button → Signature

    In the Markup toolbar, tap the + button in the bottom right. Tap "Signature" from the menu.

  4. 4

    Draw or select a saved signature

    If you've created a signature before, it appears in a list, tap it to insert. Otherwise tap "Add or Remove Signature" and draw your signature on the canvas with your finger.

  5. 5

    Drag to position and save

    Drag the signature to the correct location on the document. Resize by dragging the handles. Tap Done when finished. The signed PDF saves in the same location as the original.

Limitation: iPhone Markup doesn't let you easily see where you need to sign in a multi-page contract. The browser tool (Method 1) is better for complex documents with specific signature fields.

Method 3: Google Drive on Android (built-in)

Best for: Android users with the PDF in Google Drive.

Google Drive's PDF viewer has a basic signature feature that lets you draw and insert a signature without leaving the app.

  1. 1

    Open the PDF in Google Drive

    Find the PDF in Google Drive on your Android device and tap to open it.

  2. 2

    Tap the pencil/edit icon

    Tap the pencil icon in the bottom right corner to enter edit mode.

  3. 3

    Tap the + icon → Signature

    Tap the + button in the toolbar and select Signature from the options.

  4. 4

    Draw your signature

    Draw your signature using your finger on the canvas. Tap Adopt and Sign to confirm.

  5. 5

    Position and save

    The signature appears on the page. Drag it to the correct position. Tap Save. The signed PDF is saved to Google Drive and can be downloaded or shared.

Which method should you use?

MethodiPhoneAndroidNeeds internetBest for
1. Browser tool ★YesMost users, any PDF, any phone
2. iPhone MarkupNoQuick offline signing, email attachments
3. Google Drive✓ (app)YesPDFs already stored in Google Drive

Are phone signatures legally valid?

Electronic signatures are legally valid in most countries for most document types. In the US, the ESIGN Act (2000) and UETA give electronic signatures the same legal weight as handwritten signatures. The EU's eIDAS regulation establishes the same principle across member states.

A finger-drawn signature in a browser tool or on an iPhone meets the definition of an electronic signature, it's a deliberate act of signing associated with the document.

Exceptions: Some documents still legally require wet (ink) signatures: wills, codicils, trusts in some jurisdictions, notarized documents, court filings, and certain real estate transactions. Check the requirements for your specific document and jurisdiction before relying solely on an electronic signature.

Frequently asked questions

How do I sign a PDF sent as an email attachment on iPhone?+
Open the email, tap the PDF attachment to preview it, then tap the Share icon → Save to Files. Once it's saved, open the Sign PDF tool at imageandpdf.com in Safari, upload the file from Files, sign, and download. Reply to the email with the signed PDF attached.
Can I add initials on every page, not just a full signature?+
Yes. After drawing your initials in the signature canvas, place them on the first page, then navigate to each subsequent page and add them there. Most contracts require initials on each page alongside a full signature on the final page.
Is the signed PDF different from the original?+
The signed PDF has your signature embedded as a graphic layer on the document. The underlying text and layout remain unchanged. This is called an "electronic signature" rather than a "digital signature", it doesn't include cryptographic identity verification.
What if the PDF has a signature field I need to fill?+
PDFs with form fields (AcroForms) may have a designated signature box. The Sign PDF tool lets you position your signature anywhere on the page, including over these fields. For legally sensitive documents with specific signature requirements, verify with the requesting party that this method is acceptable.
Will the other party be able to edit the signed PDF?+
A PDF with an embedded signature image can technically be edited by the other party. If you need to prevent this, use the Protect PDF tool to add password protection after signing.

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