PDF annotations private beta 1

Getting Started

Our new app is called MetaPDF and is implemented as generic, standalone application to annotate PDFs in Google Drive:


You can also install the App from the webstore:


Feedback and reporting bugs

Please post all feedback and bugs in this thread. If you run into issues with a particular PDF (e.g. can’t open or can’t write/sync) and it is not too sensitive or private share it with andreas@paperpile.com.

Feature highlights

  • Annotations are saved natively in the PDF and can be read and edited by any standards compliant PDF program.
  • Annotations are synced back transparently to Google Drive.
  • Fully collaborative. Annotate PDF in realtime together.
  • PDFs are processed locally, i.e. the PDF is never transferred or stored on our servers.
  • Properly displayed highlight annotations that are not overlays over the text but “painted” natively on the page.
  • Streamlined UI with keyboard shortcuts (e.g. select text and try pressing 1,2,3,4) and full undo capabilities
  • Markdown support in annotations
  • Beautiful, printable summaries of all annotations in a file
  • More to come…


Step 1: Initial release as standalone app without sharing and collaboration.
Step 2: Sharing and collaboration.
Step 3: Allow opening PDFs from Paperpile in MetaPDF
Step 4: Integrate MetaPDF as Paperpile branded viewer in Paperpile.
Step 5: Show highlights and notes of PDFs in Paperpile.

Known issues

  • Currently, MetaPDF is Chrome only, will work on other browsers in the future though.
  • In the unlikely case that MetaPDF corrupts your PDF file you can revert to an earlier version within the last 30 days using the “Manage versions” feature of the Google Drive webapp.

What’s new in Beta 2

A non-comprehensive list of changes since the first beta.


  • Privacy: Fewer permissions are required (the app now only requires access to files uploaded via MetaPDF)
  • MetaPDF can now be installed via the Chrome Webstore
  • PDF files can be opened directly with MetaPDF from the Google Drive Webapp or GMail
  • Reloading of the tab will actually reload the document
  • Linkable URLs via app.metapdf.com/g/[gdrive-id],
  • Undo for all actions
  • Many more small fixes and improvements

Saving and syncing

  • Real-time saving of all changes that will be restored in a new session even when they have not been synced back to Google Drive
  • Automatic sync to Google Drive is now optional (useful for large files).
  • Check if file has changed outside of MetaPDF and ask the user if she wants to keep the version open in MetaPDF or the externally changed version in Google Drive.

Collaborative features

  • Files can be annotated collaboratively in real-time
  • Files can be shared with other users right from within MetaPDF
  • Other users can reply to comments.


  • Annotations list panel can be resized and hidden
  • Width of “Sticky” notes can be adjusted
  • Comments only show author details if multiple users have added comments. That saves space for the major use case when only one user annotates a file.
  • File can be dragged to MetaPDF right from the Chrome download bar
  • Always show current page number and total number of pages
  • Fixes for zooming
  • Improved recent files list (files that are not present in Google Drive anymore when opened will be deleted from the list)
  • Various new keyboard shortcuts


  • Full screen annotation view

  • New color scheme for highlights

  • Markdown support for notes

  • Print document with and without annotations

  • Export annotations in Text, HTML, OPML and JSON formats

  • Improved text extraction from highlights

1 Like

I can’t tell if I’m the first to reply, but I think I might be! Sweet! As always, great product! I’m looking forward to trying out the collaborative aspects.

The first little “hiccup” I found was involving exporting annotations. Upon exporting an HTML version, the resultant file is .txt. I believe it should be .html.

Thanks and congrats on the new release!

It was exciting read through the announcement. When I searched google chrome web store, I did not find metapdf.

It’s still private beta and the entry is not listed. You need to have the link:


Awesome tool!
Could you give the annotation box auto-focus once the annotation flag is clicked on highlighted text? Seems to me that whenever someone opens an annotation box for highlighted text they want to start typing immediately - this would save an extra click.

I have a pdf that does not load correctly:


We’ve found the issue with pages not showing up completely. It’s a zooming metrics issue on high resolution (retina-) displays. We are working on a fix.

After having a PDF open for an hour or so, I selected Open to start working in a new PDF. The panel opened in the center of the screen but only said 401 Unauthorized.

I refreshed the whole page and the Open option worked fine the second time. I assume there is some kind of timeout here?

When I click to add a comment a sticker appears. I start writing my note. After I’m done, using the mouse, I drag the yellow balloon to position the note. After I release the mouse button the comment box is updated and shows nothing, my note is lost! Oh wait, if I drag the yellow ballon again somewhere else, my note text reappears. It was not lost after all!


Nice catch. Yes, there is a timeout of exactly one hour for the authentication with Google services. We transparently renew the authorization behind the scenes when necessary. But we have not covered the case of the open dialog. We will fix that.

We can reproduce. It’s a weird race condition. Should be an easy fix. Thanks!

We’ve fixed the retina issue and it should load fine now. If not let us know, thanks!

Page titles are not consistent like in Paperpile. Here are 3 papers opened in PP and MetaPDF side by side:

At the moment MetaPDF does not know anything about the data in Paperpile and therefore can’t show the title like Paperpile which knows the bibliographic data of the PDF.

Annotation Filters

Great work on the annotations. The ability to export your annotations in a variety of formats is awesome and some that even the most expensive PDF tools cannot do well (cough…Acrobat…cough).

I was thinking that since your annotation exporting features are so good, why not take it a little further. It would be great if on the annotation export screen, there was an option to apply various filters. Perhaps it would be handy to filter by:

  • A range of page numbers
  • A range of annotation creation dates
  • A range of bookmarks (I don’t know how this would work, but it would be great to export only the annotations from a certain chapter.)
  • My annotations and/or other people annotations
  • Annotations containing a certain word
  • etc.

Let me know what you think!


I very much appreciate being part of the beta & I really like what I have seen from MetaPDF so far.

Just a small thing I noticed. I highlighted some text on a PDF, saved it, and then downloaded the file to my hard drive. When opening the PDF in Adobe Reader (v11.0.1) the highlighted area was displayed differently depending on the level of zoom. This doesn’t happen in MetaPDF or Google Drive. I don’t currently have permission to post a picture, but basically the highlighting doesn’t cover all of the text when I change the zoom away from 100% in Adobe Reader.

Some issues that I’m finding:

  1. Most of the pdfs are showing up “fuzzy” in metaPDF, despite being crisp and clear in default chrome browser. This is caused by the Chrome zoom setting not being 100%. I know you know about the issue, but I hope that it is something you plan to address. Even a popup message reminding folks to reset to 100% would be good for the time being, because I"m sure others will forget like I did.

  2. When Chrome zoom isn’t set to 100%, then highlighting is seriously wonky. The cursor doesn’t always change to from the arrow to the text selector, and even when it does it’s got some sort of calibration issue. The highlight is either showing up a line above where I click, or is off-centered (sometimes up, sometimes down) sometimes it will select multiple words to the the left of where I’m clicking and dragging. Again, the solution is to set to 100%, but for new users who, like me, almost never have my chrome browser set to 100%, it may turn them off.

Little stuff: The colors in the annotation bar on the left are still using the original deeper colors. They’re pretty, but not the same as the actual highlighting colors used, and so cause a moment of confusion and longer visual search.

I think that’s all. Looking much better! Can’t wait for this to be integrated into Paperpile.

I typically use the arrow keys to scroll throughout the document, but this currently does not work (also not after clicking on the pdf itself to ensure that it is in focus). Could you please add this if possible?

Besides this I have not run into many problems and am very much enjoying the use of MetaPDF :smile:

It would help a lot if you could send a screen shot to andreas@paperpile.com.

@chjh @mpezzo

We just pushed another update that should address the key up/key down navigation and the issue with making highlights when the browser zoom level is not set to 100%.

The issue of the rendered PDF being blurry when the zoom level is not set to 100% is something that is inherent when zooming with the browser. The browser takes the rendered PDF page (an HTML canvas element) and the simply scales it, which makes it look blurry.