Tuesday, September 14, 2004

The Future of Mobile Computing

Neil's PDAThoughts over at PDA24/7 caused me to waste an hour this morning. Here are the fruits of my thoughts under three headings: Size, Input and Connectivity.

If the computer is not as convenient to carry and use as a paper PIM, then users will use both (this is the current situation with many laptop users). As with paper PIMs, there will be demand for a range of sizes: people who like big desk diaries may be happy with a sub-notebook size mobile computer, but people who have slim pocket diaries will want something closer in form factor to a Palm Vx. But note that if you try to fit the functionality of a desk diary into a pocket diary, it becomes hard to use; similarly, we can expect the smaller PDAs to have less functionality (at a lower price) and the bulkier ones to do more. I think PalmOne is the only PDA manufacturer who fully understands this point (e.g. the m100 and the Zire), but it is having trouble keeping the size down since the move to colour screens and audio output. Go to a stationers and look at the display of diaries and Filofaxes: a mature PDA market will see a similar range in size of device and complexity of function.

It must be easy to scribble a phone number or whatever onto the device otherwise users will find themselves carrying pen and paper as well. In other words, truly ubiquitous mobile computers have to replace many of the other things we carry in our pockets. However, many users will be happy with scribbling info into a notepad application and entering it into the PIM applications later. More important than raw data input is the ability to make, change and move appointments with ease. In particular, many users find it difficult to browse through a PDA calendar to find a free slot for a meeting – but in fact there are similar problems with many desktop PIMs. This is a software issue: we need good multi-day views and the ability to riffle through 'pages' quickly while keeping track of the date.

Note-taking is different: I don't think a computer, any computer, can replace pencil and paper for most people, so there is not much point in trying. As a university lecturer I see a lot of students taking notes. Many carry laptops around with them, but in 10 years I have only ever seen two take notes on a laptop during lectures, and I have never seen any student take notes on a laptop during a seminar. They have the option, but they prefer pencil and paper. (In fact a much more common use of technology is to record lectures.) Moral: if users choose not to take notes on a laptop when it is there in front of them, they are not going to take notes on a PDA. The majority of users will only want to input small amounts of data (100 words or so) directly onto a PDA, so good handwriting recognition will suffice.

I split this into two: Transfer of Data and Communication

Transfer of Data
Power users of PDAs soon realize that their most amazing ability is to carry very large amounts of data, be it documents, web pages, reference manuals, photos or music. One very important use of connectivity is to download and update this data. For me this is easy: I spend most of my day sitting at a desktop computer with fast internet access and my software running on it, so Hotsync type of technology suffices. But plenty of other users will want to be able to transfer data to a PDA without a desktop. However I still think that this is not a mass market – example: how many people get weather forecast information from a newspaper (which is at least 12 hours out of date) or from the TV (which requires one to wait until a weather bulletin), rather than off the internet which is instant and bang up to date? Such users are unlikely to pay extra, either in hardware or subscription charges, to be able to transfer data to their handhelds 'any time any place'. Oh, and it is worth mentioning that anyone who thinks 'geek' is an insult will not be interested in browsing the web on anything smaller than a 17" screen.

Email is very popular amongst people who work on computers because it is quick but has the advantage of not disturbing the recipient and making it very easy to be concise (cut the chatter). It is also popular as an alternative to writing personal and business letters. Neither of these uses suggest that there is much demand for email on a device which you carry with you always.

IM, SMS and voice are very different sorts of communication technology: they demand immediate attention (and often immediate responses) from the recipient, they are chatty, but they are inappropriate for more formal communication. Phones do SMS and voice brilliantly, and when we get 3G networks, I expect we will see IM on phones as well. This appears to imply that there is a good reason to have convergent devices, or at least ones which put the phone and the computer in the same box. And it seems that is what the electronics world is betting on at the moment. But I see two problems with convergent devices:

(1) a PDA and a phone have different ergonomic requirements: a PDA is effectively an electronic book, a slab which you hold flat on the palm of your hand and look at, whereas a phone is held in a finger grip and placed against your head where it cannot be seen;
(2) phones can be either 'business' or 'personal' but most people want to keep these functions apart because they want to keep these aspects of their life apart, which means that if you give someone your work number you don't want them to be disturbing you while you are playing with your kids. But PDAs are different: because they are primarily passive resources blending 'business' and 'personal' is a positive help in keeping your life balanced and being in control. Communication devices allow others to put pressure on you and thus work and family are best kept apart (it is worth noting that usually we want to keep work pressures out of family life, but sometimes we do want to keep family pressures out of work life). Information devices allow you to make decisions and take critical actions, so nothing should be excluded.

Let me give an example of the last point: your kid falls off his bike and cracks his head on a Sunday evening, so you spend 3 hours waiting in A&E. You realize that he won't be able to go to school to-morrow so either you or your wife will need to take time off work. With your PDA you have all the information you need to make the decisions and phone calls. It does not matter whether you make the calls from your own phone, your work phone, a borrowed phone or a payphone in the hospital – you just need the information to do it.

For most people, I think it is unwise to merge information and communication devices, because these have very very different roles in our lives. A substantial minority of people may be prepared to pay to have the data on their handhelds updated 'any time any place', but the majority will settle for connection via a desktop.

Carrying around a computer does not replace paper note-taking, so the data input requirements on such a device are limited to appointments and scribbled notes and maybe a little editing of existing documents in response to new information or ideas. And in general, there will be the same trade-off between size and functionality that we find with paper PIMs: some want the smallest possible, others want the most functional. So be it.