Local PDF tool - browser processing

Sign an NDA on your phone without uploading

When you just need to add a visual signature to an NDA, use the responsive Sign tool and keep the PDF processing in the browser.

Open Sign mode See the proof

0 bytes sent proof

What the widget measures

The panel counts what leaves your browser after you choose a file. The site's own scripts and fonts load like any web page — what you will never see is a request carrying your PDF. Check it here, or open your browser's Network tab and see for yourself.

0 bytes of your document sentStarts measuring when you choose a file on a tool page
Document request bodies
0 bytes
App network after file open
0 bytes
Processing engine
Browser WASM worker

The number is scoped to request bodies after you choose a document. App assets such as JavaScript, WASM, and fonts can still load; those are not your PDF bytes.

Verify it yourself
  1. Open DevTools, then the Network tab.
  2. Choose a PDF in the tool and complete the action.
  3. Filter for fetch or XHR requests; document processing should not create a request carrying your file.

Stronger check: load the tool page first, then disconnect from the network before choosing the file. Already-loaded tool code can continue processing locally, but a first visit still needs the site assets.

Steps

How to do it in Lemmafour

  1. Choose Open Sign mode on the phone.
  2. Tap Choose PDF and select the NDA from local files.
  3. Create a signature in Signature Studio or import a signature image.
  4. Tap Add signature, place it on the signature line, and adjust the size.
  5. Apply signatures, then use Download or share the saved file from the browser.

Expert note

Mobile signing risks

The hard part on a phone is placement precision, not processing privacy. Zoom in before applying the signature, check that the date and initials do not cover contract text, and reopen the downloaded file before sending it. A visual NDA signature still does not add certificate validation or signer identity proof.

FAQ

Questions people ask before using this tool

Can I use this in mobile Safari or Chrome?

The tool is built for responsive browser use. File picking and download behavior still depends on the mobile browser.

Does airplane mode work?

Load the tool page first, then go offline before choosing the NDA. First-time asset loading still needs the network.

Is it legally binding?

Lemmafour does not give legal advice. The tool adds visible signature content; legal effect depends on your situation and requirements.

Related private PDF workflows

Keep working locally

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