Review of iAnnotate


Recently I tried an experiment with one of our iPads to read and review a journal submission using the iAnnotate application. For the purposes of review, I had to read and comment on the draft, and then write up the review. I approached the problem much like I would had I been reading on paper, which included highlighting important, controversial or confusing passages, writing comments and reactions in the margins, and flipping around the document. These were all activities we had supported in XLibris, and I was curious how the iPad would stack up.

The short of it is: loading documents: OK; readability: Great; inking: poor; highlighting: poor; text annotations: OK; within-document navigation: so-so; between-document navigation: OK. Overall: good for reading, not good for active reading.

Loading documents

Getting documents onto the iPad for the iAnnotate software to use is not trivial. For reasons unclear to me, it is not possible to browse to a web page with a link to a PDF file and then transfer that PDF file to the device for reading and annotation. In fact, there seems to be no way to save a document onto the device from the browser. Instead, one has to install a server on a networked computer to which the iPad has access. Once installed, the server is used to make certain directories available to iAnnotate app, from which it sucks down PDF files.

The process is a bit tedious but not too bad. There are some synchronization issues between the iAnnotate app and the server. At one point, the iAnnotate application was not seeing the server until I started VPN and restarted the application. I don’t know why connecting to VPN was required, or why the server wasn’t seen without restarting the application. iAnnotate did not see the server when I was at work (and thus at a different IP address). Back at home, I wasn’t able to reconnect to the server without quitting and restarting it.

One other annoying feature was that after the documents are loaded through the “get documents” menu, you cannot open them directly; instead you must tap the “+” button at the top left of the screen to add a new tab, and then navigate to the newly-uploaded documents again.


The first thing I noted that the document is quite readable on the iPad. Granted, it was a typical double-spaced journal article manuscript, but none-the-less, it was very readable even when zoomed out to show the full margins. A two-column conference formatted paper is also legible, although obviously not as nice.

The full-screen mode made it easy to read the document without the widgets getting in the way.


The iAnnotate application supports two kinds of ink: thin free-form pen-like strokes, and thick translucent highlighter marks that correspond to text. I tried to use both in the course of my reading, with so-so results. First, it should be said that the iPad is inherently not designed for using a stylus. Yes, one can use a stylus with it (I used a Pogo Sketch stylus), but because the display is designed for touching with a relatively fat finger, the stylus tip is also relatively fat (compared to tips for tablet PC styluses, for example). The tip is so large that it obscures the point of contact with the screen, making it difficult to write.

In addition to this occlusion problem, the CPU (or perhaps the iAnnotate application) is just not fast enough to track the stylus when it is used to write. One can make broad circles and margin bars which look fine, but any kind of fine manipulation has sufficient lack to make effective writing impossible. Another problem with writing on the screen was that resting the hand on the screen often confused the digitizer, causing spurious marks to appear on the screen.

Highlighting works better in some ways because it is constrained to the bounding boxes of the text; thus when the boxes are available, they get a nice yellow color to them which makes the text stand out nicely. The downside is that if the text bounding boxes are not available for some reason, the highlighter doesn’t work! The document I was reading, for example, for some reason did not have valid bounding boxes for regular text, although italic text was properly characterized. The result was that I could highlight only italicized text! Furthermore, I could not highlight any text that was in figures which were generated as images rather than containing regular text. Overall, therefore, highlighting proved to be something of a dud.

Text annotations

Text annotations were easy to create and straightforward to type on the soft keyboard. They could be displayed in a floating dialog box over the text, or reduced to a small icon. Unfortunately, the floating dialog obscured the document, and the icon required tapping to show the text. I would prefer an option where the text, if there isn’t too much of it, is shown overlaid on the document using a translucent post-it or something like that. The idea is that the text and the document should be readable at a glance without requiring any interaction.

Within-document navigation

Scrolling within the document was fine from page to page, although I would prefer for motion to be constrained to the vertical dimension when scrolling between pages. It was a bit disorienting to have the page move from side to side at the same time.

Navigating via annotations was not as good. Annotations were available through a sub-menu of the main menu, but the list of annotations showed the text of textual annotations (which was good) but only the word “annotation” for ink. Thus it was impossible to tell which menu item linked to which passage (although the page number was occasionally useful). I really missed the notebook view in XLibris for reviewing what I had read and marked up.

Between-document navigation

Each document was kept in a separate tab, making it easy to switch between documents, although no more than six tabs could be opened at any time. I don’t know if this is a major problem, however. It  certainly didn’t come up in my reading.


The iPad is a nice device for reading, but the iAnnotate application is not ready for prime time with respect to annotation for the purposes of making sense of and navigating through documents. It’s not clear whether the limitations are inherent in the design of the hardware, or whether some clever optimizations for creating ink will mitigate some of the shortcomings described above. In any case, reliance on a stylus when the device wasn’t truly designed for it will limit overall ease of use.


  1. Papers or GoodReader or several other apps work well for the reading side (and can pull from DropBox or Bonjour or iTunes – Papers will fetch from the ACM DL or Scholar). The problem is in the inking…it seems to be overlooked in most of the other apps. Hopefully someone will figure out its kinda important.

  2. It seems that a lot of products focus on rendering, some on navigation, and very few on other aspects of active reading such as annotation, note-taking, etc. Yet those activities are exactly the ones that can benefit most from the presence of the computer. Otherwise, you might as well read on paper.

  3. [...] a follow-up to my review of iAnnotate, I did a quick exploration of drawing apps available for the iPad to understand the limitations of [...]

  4. Reviewing conference/journal papers on (a desktop) screen only became productive for me at a minimum screen resolution of 1900×1200. At lower resolutions, there simply wasn’t enough space to render enough of the document and my own notes simultaneously. I don’t have high hopes that 1/3rd of pixels compounded with fat finger, soft keyboard and other input challenges can rival the desktop reviewing experience anytime soon. I’ve had success on the iPad though with a) reading longer, less densely formatted texts while taking only occasional notes; b) “passive” reading of already-published conference papers.

  5. Reviewing off a desktop monitor seems painful to me; I would much rather print & read off paper. The the promise of the slate format is a more tangible reading & marking experience, but that has to be supplemented with computational augmentation before it can rival paper. Augmentation may also improve the desktop experience, but that seems like a higher hurdle for reading, particularly for reading large amounts of text, as it limits both mobility (you’re stuck in your office) and micro-mobility (you’re stuck in essentially one position in your chair).

  6. Hey Guys, We just updated iAnnotate and worked on addressing the issues that you mentioned!

    Here’s a quick run through of a few changes:

    - A redesigned and streamlined interface
    - You can receive, modify and send annotated docs through email!
    - Transfer PDFs via iTunes USB
    - Download any PDF link with the integrated web browser
    - Share files with other apps.
    - A redesigned document finder now includes favorites, tag search, new/recent documents, and more.
    - Text annotation summaries are available to read and share.
    - Two finger scroll allows lets you scroll while editing
    - Many other minor interface improvements and bug fixes based on excellent user feedback!

    We’d love to know what you think, and we’re super attentive to our forums if you have any questions at all.

  7. [...] couple of weeks ago I wrote about iAnnotate, a document annotation app for the iPad. On Friday, the folks who develop the app [...]

  8. Hey folks,

    We’ve launched somewhat of a free version of iAnnotate called iRead. It has shot up to the top 40 overall apps in less than 2 days, and it allows a lot of the features that make iAnnotate great.


    - full-featured PDF reading
    - easy PDF transferring via email and iTunes sync
    - fully customizable toolbars
    - tabbed PDF reading
    - document and full-library search

    So if you were on the fence for iAnnotate, be sure to check iRead out and tell us your thoughts!


    iTunes link:

  9. Thanks for the note! I will definitely take a look. And thanks for updating us on your progress with iAnnotate as well.

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