My good friend David Headley of that splendid London institution the <a href="http://www.goldsborobooks.com/" target="_blank">Goldsboro book store</a> asked me on Twitter yesterday, 'Can you edit a book on an iPad?' The only answer I feel able to give within the limitation of 140 characters is: no.

I tried when I first got my iPad a few months ago and failed miserably. But time, and software, moves on. I have another MS to read. So I thought I'd give it another go. And the answer this time has to be... perhaps. If you accept the limitations and you choose the right software.<!--more-->

Let's deal with a simple issue first: can you import a Word document and edit it in a safe way? Not in any way I'd trust. Pages on the iPad will open Word. But you have no change tracking or comments, as you have on the Mac version of Pages. All you can do is change the text. Using a very unsatisfactory keyboard. With no revision history. You'd be mad to try frankly.

So however you look at it the only way to deal with this is by reading and annotating a pdf. Fine, but let's think of the practical limitations. I always print out a manuscript and go through it line by line, page by page, with a red pen in hand. Nothing will cure me of that habit. But I read and reread a MS and I'm open to the idea that at least one or two of those passes could be handled digitally.

The problem is we think marking up a paper MS with a red pen is a simple exercise. It isn't. Think of it this way: you can hold that pen and turn the page, scratch your nose, answer the phone, drink a cup of coffee. Computers aren't that smart. No tablet I've seen yet has come with the obvious mechanical tool to turn pages -- up and down buttons. You have to swipe or tap the screen somehow. Oh, but that's how you use the pen too. So you have to do something to choose between these actions and <em>tell</em> that dumb piece of plastic, 'No, I've stopped scribbling now. Take me to the next page'.

<a href="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/photo-11.png"><img class="alignright size-medium wp-image-6686" title="iAnnotate" src="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/photo-11.png?w=225" alt="" width="225" height="300" /></a>This was what drove me nuts with the first iPad pdf app I tried, iAnnotate. You can flick through pages easily but when you want to annotate it looks like this...

Click for a bigger view. Someone has been taking the icon pills for this app. Everything seems to come with whacking great pictures and text boxes. All I want to do is circle a word or scribble a note. But to do that I have to flick the pen icon, see that hideously big lump of stuff appear on the screen -- which I find deeply distracting -- make my scribble then click the gigantic red close button to make it go away.

That was money wasted (you have to buy iPad apps before you can try them, a neat trick I must say). I experimented with a few other pdf apps after that and none of them seemed particularly convincing. But there've been some updates of late and here, I think, are two that are worth a look, <a href="http://www.goodiware.com/goodreader.html" target="_blank">Goodreader</a> ($2.99) and <a href="http://readdle.com/pdfexpert_ipad" target="_blank">PDF Expert</a> ($9.99).

These are both powerful pieces of software that do a lot of things I don't need or frankly understand. All I want is to be able to flick through a long pdf manuscript and make notes and bookmarks.

The cheaper one first. Goodreader doesn't get in your way when you're reading a manuscript. You just place your finger on the spot where you want to make your annotation. The word may be selected (I'm not quite sure how this works) and you get this menu.

<a href="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/goodrdedit1.jpg"><img class="aligncenter size-full wp-image-6689" title="goodrdedit" src="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/goodrdedit1.jpg" alt="" width="490" height="215" /></a>As you can see in the preceding paragraph I've crossed out the word 'dish'. I did this by choosing markup and delete. You can write a note, highlight the text or draw -- in other words scribble some words. Do that and it looks like this...

<a href="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/goodreadann1.png"><img class="aligncenter size-full wp-image-6690" title="goodreadann" src="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/goodreadann1.png" alt="" width="490" height="194" /></a>I used an inexpensive stylus to write that. But you could just use your finger. It all worked fine but you do have to flick through a lot of menus to get to freehand drawing in Goodreader. If you want to scribble on your manuscript a lot this could get tedious.

PDF Expert has very much the same idea. Click on a word or line and you get this.

<a href="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/pdfexpert1.png"><img class="aligncenter size-full wp-image-6691" title="pdfexpert" src="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/pdfexpert1.png" alt="" width="490" height="151" /></a><a href="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/pdfnote1.png"><img class="alignright size-medium wp-image-6692" title="pdfnote" src="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/pdfnote1.png?w=225" alt="" width="225" height="300" /></a>Click on Note and you get a rather nattier looking note feature than Goodreader (though in practice they do the same thing).

I did like this pop-up note feature on both programs, by the way, especially PDF Expert. It seemed easy and logical. PDF Expert also puts a little icon on the side of the page which is rather more obvious than the small mark you get with Goodreader. Agents and publishers, who will approach manuscript revisions in a different way to authors, might find these particularly useful. They're good for general observations, not the individual word criticism an author might make at revision stage.

Writing freehand is <em>much</em> easier with this app than in Goodreader. You just tap at the top of the screen and get this menu which hides normally when you're reading. The first pen is a freehand drawing tool (the second is for signatures, the third for help, the fourth searches, the fifth bookmarks, and the plus sign will set a bookmark).

<a href="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/pdfdraw1.jpg"><img class="aligncenter size-full wp-image-6693" title="pdfdraw" src="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/pdfdraw1.jpg" alt="" width="490" height="527" /></a>The help function is excellent too.

<a href="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/pdftools1.jpg"><img class="aligncenter size-full wp-image-6694" title="pdftools" src="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/pdftools1.jpg" alt="" width="490" height="483" /></a>

Here's a little video showing you PDF Expert in action on next year's book, <em>The Plague Doctor.</em>

You get what you pay for I guess. Goodreader's excellent value but if I were to use the iPad for revision a lot I think the $9.99 (£5.99 when I bought it in the UK) is worthwhile. PDF Expert is very simple to use and very logically designed. Both these apps will work with a Dropbox account for sending and receiving files which is a real blessing given how hard it can be to get stuff on and off the iPad (I had to email those screenshots to myself for pity's sake). A decent stylus would be useful for anyone wanting to scribble a lot. I bought a Boxwave stylus because the reviews said it was the best. Don't much like it. If there's nothing better than that I guess it's back to trying to write with a fingertip, which isn't wonderful.

Can this completely replace pen and paper? Not for me. Not for a while anyway. But it's getting closer. And here's the most intriguing thing that occurred to me. Stupidly I kept thinking I'd transfer the annotated pdf back to the computer and read it there against the uncorrected manuscript, dealing with the changes along the way.

But why? Pop the iPad into a stand, set it next to your main screen and use it like an old-fashioned copy holder, checking revision notes there against the original on your Mac or PC. <em>This I like.</em>

<a href="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/mac1.jpg"><img class="alignnone size-large wp-image-6695" title="mac" src="http://vir.liquidweb.com/~davidhe4/davidhewson.com//wp-content/uploads/2011/01/mac1.jpg?w=640" alt="" width="640" height="404" /></a>

I hope that long-winded ramble answers some of your questions, David. We are getting there but, given that iPad 2 is just round the corner, along with a lot of Android and Windows tablets, my inclination right now would be to wait for the next generation of machines before making the leap.