How to annotate PDF on iPhone, Android, or iPad

What this workflow helps you do

A phone browser can run Annotate PDF without a separate desktop program. Device memory, the mobile file picker, camera permissions, and download handling matter more on a phone, so smaller batches are easier to verify.

Choose a PDF on a phone or tablet, place a highlight and note, and download the annotated copy.

Plan the task in Annotate PDF

Mark a selected PDF page with a visible highlight and optional note, then create a new annotated document locally in your browser.

Annotate PDF is a focused review tool that places a coloured page-width highlight band on one selected page and can include a short note. It produces a new shareable copy while leaving the source document unchanged.

1. Highlight a PDF page during review. Use the visible band to draw attention to a relevant area or page in a report, assignment, proof, or approval workflow.
2. Add a short PDF note. Include a concise comment with the annotation so the recipient understands why the page was marked.
3. Understand the current annotation scope. This version does not provide freehand drawing, arbitrary text selection, or a full multi-annotation workspace. It applies one focused page annotation per run.

Complete the task reliably on a phone

The mobile file picker may show Photos, Files, Downloads, a camera option, or cloud-provider shortcuts depending on the device. Select only the sources required by Annotate PDF and return to the browser while processing finishes.

Large documents and high-resolution images use device memory. If the browser reloads or becomes unresponsive, keep the originals and retry with a smaller supported batch rather than repeatedly starting the same large job.

1. Use a current browser and keep the tab active during processing.
2. Save the result to Files or Downloads.
3. Reopen the download outside the tool before sharing it.

Settings and limitations to check

Can I annotate a PDF online for free? Yes. Add a supported highlight and optional note without registration.

Can I select individual words to highlight? No. The current tool creates a page-width highlight band rather than a freehand or text-selection highlight.

Does annotation change the original PDF? No. It creates a new annotated copy and leaves the selected source document unchanged.

1. Use only the settings needed for the required result.
2. Keep the source file available for comparison.
3. Do not rely on an unsupported exact-size, fidelity, or security promise.

Review the completed file

Reopen the result on the device and verify placement at a comfortable zoom.

Open the downloaded result in a separate viewer, inspect important pages or details, and repeat the workflow with adjusted settings if the output is not suitable.

1. Confirm the expected file type and page count.
2. Check important text, images, order, and orientation.
3. Share or submit only the reviewed copy.