# What are PDF annotations, and can you see them on a phone? — DocFind Last reviewed: October 10, 2026. HTML version: https://docfindapp.com/answers/pdf-annotations **Annotations are the marks people add on top of a PDF's pages: highlights, sticky notes, speech bubbles, drawings, shapes, stamps and signatures. They sit over the text rather than changing it, which is why Acrobat calls most of them comments.** A phone can usually show them, but two things decide it: whether the annotations were saved as editable marks or flattened into the page, and whether the app you open the file in draws them or lists them. ## What counts as an annotation

Apple's Mac guide draws the line clearly: "Although you can’t edit the text of a PDF in Preview, you can use the markup tools to provide feedback or write down something you want to remember" ([*Annotate a PDF in Preview on Mac*, Preview User Guide](https://support.apple.com/guide/preview/annotate-a-pdf-prvw11580/mac), read 10 October 2026). Its iPhone guide lists the kinds you can add on a phone: you can "copy, highlight, underline, or strike through text in a PDF file", and "annotate a PDF or image with stickers, signatures, shapes, or text" ([*Annotate a PDF or image in Preview on iPhone*, iPhone User Guide](https://support.apple.com/guide/iphone/annotate-a-pdf-or-image-iph73ca5c8e6/ios), read 10 October 2026). Notes are their own type. Apple says "You can use notes and speech bubbles to comment on text in a PDF", and each note carries an author name, which Preview fills in from your Mac login name unless you change it in Preview's PDF settings ([*Add notes and speech bubbles to a PDF in Preview on Mac*, Preview User Guide](https://support.apple.com/guide/preview/add-notes-and-speech-bubbles-to-a-pdf-prvw7450efd7/mac), read 10 October 2026). That last detail is worth remembering before you send an annotated file to someone outside your organisation.

## Editable or flattened: the choice that decides what others see

Apple spells out the two ways a marked-up PDF can be saved. "To save a PDF and allow annotations to be edited later, choose one of the following: File > Save, File > Export, or File > Export to PDF." To fix them in place instead: "To save a PDF and flatten annotations (so that they can’t be edited), choose File > Print, then select Save as PDF" (the *Annotate a PDF in Preview on Mac* page above).

What that means for a phone: a flattened mark has become part of the page, so any viewer that shows the page shows the mark, but nobody can select, move or delete it any more. An editable annotation stays a separate object, and it appears only if the app you use chooses to draw it. If a colleague's notes are missing on your phone, ask whether the file was flattened, or open it in a fuller PDF app.

## Seeing all of them in one list

On a Mac, Preview collects notes in its sidebar: "Choose View > Highlights and Notes", and "All the notes in the document are displayed in the sidebar" (the *Add notes and speech bubbles* page above). Acrobat on a computer has a Comments list that "displays all comments in a PDF" with sorting and filtering, and from its options menu you can "select Print with Comment Summary" or "select Export to Word" ([*View comments*, Acrobat Desktop Help](https://helpx.adobe.com/acrobat/desktop/share-and-review-documents/manage-reviews/view-comments.html), read 10 October 2026).

Acrobat on a phone has a list too, described for shared reviews: "Open the shared PDF and select Comments from the top menu", then "tap a comment to jump to its location in the document". Adobe adds that "To add, edit, or delete comments, sign in with your Adobe ID". The page is written about PDFs shared for review and does not say whether the same list appears for a file you simply opened from your phone ([*Manage comments in Acrobat on mobile*, Adobe Acrobat Help](https://helpx.adobe.com/acrobat/mobile/review-files/manage-comments.html), read 10 October 2026).

## On an Android phone: the Show annotations switch

Google's two PDF tools on Android each have a toggle. In the Google Drive app, "To show or hide all annotations, select Show annotations or Hide annotations" ([*Annotate PDFs with a stylus or freehand on Android*, Google Drive Help](https://support.google.com/drive/answer/13207179?hl=en), read 10 October 2026). Files by Google has the same pair, "Show annotations" and "Hide annotations" ([*Open, manage & edit PDFs in Files by Google*, Files by Google Help](https://support.google.com/files/answer/15949407?hl=en), read 10 October 2026). So if a PDF looks bare in either app, check that switch first. Neither page says whether "all annotations" includes notes and comments added in other programs, such as Acrobat's sticky notes, or only the pen and highlighter marks drawn in Google's own tools.

Both pages also say what happens when you add your own marks. Drive offers to "save the original PDF or make a new copy with a new name", and with a new name "the original copy remains unmarked". In Files by Google, "When you save a copy, it’s uploaded to your Google Drive", while "the original copy remains unmarked and saved on your device".

## On an iPhone

Apple's iPhone guide to Preview is about adding marks: highlighting selected text, adding stickers, signatures, shapes or text, and undoing a change (the *Annotate a PDF or image in Preview on iPhone* page above). It does not describe a list of a document's notes like the Mac's sidebar, and it does not say how notes made in another app are shown. If you are reviewing a document someone else commented on, Acrobat's comment list, described above, is the documented way to see every comment on a phone. To add highlights of your own, [highlighting a PDF on a phone](https://docfindapp.com/answers/highlight-a-pdf) has each app's steps.

Related: [Highlight a PDF on a phone](https://docfindapp.com/answers/highlight-a-pdf) · [Copy text from a PDF on iPhone](https://docfindapp.com/answers/copy-text-from-pdf-on-iphone) · [What is a PDF file?](https://docfindapp.com/answers/what-is-a-pdf-file) · [Which app is best for a PDF viewer?](https://docfindapp.com/answers/which-app-is-best-for-pdf-viewer)