Maximizing user experience of the Mobile Internet

Now a user can always stay connected without blocking incoming calls, and s/he normally does not pay for the waiting time but only for the received content.

There are about 0.5 million Mobile Internet pages (WAP and I-mode) at the moment, and about 3 billion Web pages on the Internet. For some people, the relative size of the Mobile Internet means that finding specific information is easier than from the full Web, but many others would still want to have mobile access to the full Web in its entirety.

Through research, Nokia is investigating how to merge the best of both worlds. Already now, test users have been positively surprised that viewing full Web pages on a small screen is not as bad an experience as they expected.

Three systems - One user experience

A fundamental principle in achieving our goal is that users are interested in the content, and all other parts of the system should be invisible. When a person is accessing WAP or Web pages through a mobile phone, the device, the browser, and the site need to work fluently together to provide a usable experience.

Improved WAP browsing
Over the years, Nokia Research Center has conducted tens of usability studies on different kinds of WAP sites to find out the best practices for building Mobile Internet sites. Based on these studies, we then provide guidelines for site developers at Forum Nokia. The latest recommendations are documented in WAP Service Developer's Guide for Nokia Series 40 Phones with XHTML Browser [1].

The move from WAP 1.x sites written in WML (Wireless Markup Language) to WAP 2.0 sites written in XHTML Mobile Profile (eXtensible Hypertext Markup Language) makes it possible for the user to view the same site both on a mobile device and on a PC. The biggest impact of WAP 2.0 on usability is the fact that XHTML MP pages are downloaded one by one, not as a deck of cards (as in WAP 1.x). Because requesting the next XHTML MP page takes longer time than requesting the next card in the already-downloaded deck, it is important not to copy very short cards to XHTML pages as such. Longer pages are more usable in WAP 2.0 [2].

Navigating

We are often asked about the optimal number of links on a navigational page. The old usability rule has been 7 (+/- 2) items in a menu, but it seems this is not the best rule with links on a WAP page. In most cases, it is better to have 12 links on a page and a site hierarchy of 3 levels than 7 links on a page and 4 hierarchical levels. Actually up to 30 links can be shown on a page, provided that they are tightly bound together and they can be listed in a logical order. An example would be a list of cities in alphabetical order. If there are more than 30 items on the list, do not just split the items onto several pages and expect the user to download pages one after each other, but offer the user smarter navigation methods or a field to type the value.

Finding content

While navigational link pages cannot be too long, informative pages should provide enough information. We have tested a page that was 20 screenfuls long, and the participants were pleased to get enough information after making the effort to navigate to the page.

When trying to find the desired information on the site, more than half of the users utilized a keyword search when it was provided easily [3]. This is surprising, considering the effort required to enter text with a standard ITU-T keypad. So it is important to provide a search function also on Mobile Internet sites.

Using graphics

Now that most new phone models have a color screen, it is very tempting to build sites that are as graphical as current Web pages. Our studies show, however, that users are dissatisfied with graphical mobile sites if the graphics do not provide added value [4]. Images do create a 'wow effect' when seen for the first time, but if users cannot use the site until the images are downloaded they very quickly get frustrated. Our recommendation is to design for the case where the user has set 'Images off' from the preferences; this way it is guaranteed that the user does not have to wait for the images if s/he just wants efficiency.

Browsing the Web on small screens

Many mobile users also want to access Internet information not currently available through WAP, but since most Web pages are designed for large screens, this is inconvenient. The number of mobile-tailored Web pages should increase as more users get a taste of accessing the full Web with their mobile devices and more companies provide mobile versions of their sites.

Until we have enough mobile-tailored sites out there, we have to investigate the methods for viewing large Web pages on small displays. The two major methods that are used today are Original Layout and Narrow Layout.

Original Layout shows the page in the format it is shown on a PC screen. The user can scroll horizontally and vertically to see different parts of the page. Several viewing options can be provided to help finding information on the page, such as zooming or positioning the view to the most relevant point on the page.

Narrow Layout is a method where the Web page is columnized to fit the width of the small display. This way, the need for horizontal scroll is eliminated; the user will see all the content just by scrolling down.

In our tests, it seems that both of these methods have usability problems. With original layout, users get easily lost on the page, especially if there is lot of white space on the page. Users want to zoom in and out to get an overall view of the page. But because most mobile phones do not provide a special zoom key, zooming in and out is laborious or at least hard to learn.

Narrow layout needs extensive scrolling, but most mobile phones do not provide efficient scrolling mechanisms like acceleration if the down key is pressed continuously [5].

Both layout methods suffer from a keyhole view effect: you cannot concentrate on one part of the page only, but need to scroll through irrelevant information to get there. It is hard to say if the page has changed at all when you navigate within one site with exactly the same top of the page shown to you on the first screenful. (You can see this effect by making your PC browser small and trying to navigate certain Web sites where the dynamic content is not on the top left corner of the page, like when using the 'Select FAQ Category' on the Nokia Research & Venturing FAQ page).

In spite of the usability problems, our test users have been positively surprised that viewing full Web pages on a small screen is not as bad an experience as they expected. We do believe that it is possible to view Web pages on small screens without major difficulties; we just need even better viewing methods. In this quest, we are investigating ways to give more control to the user in selecting the page area s/he wants to view, but also ways to automatically provide that area for her/him.