Prior to the release of S60 3rd Edition, Feature Pack 2 the S60 UI offered very few dynamic graphic elements. The few that existed were limited largely to animated screen savers and wallpaper. Enter Kastor from TAT, a UI rendering engine. "Kastor has allowed Nokia to make the S60 more expressive," says Hampus. "Our technology has enabled new dynamic effects and we have done it without adding memory and processor requirements to S60 devices."

It is not uncommon for UI changes of this type to create problems for developers, because new features may not fit well with the existing APIs. However, Nokia set a clear goal that the integration should not break source or binary compatibility with earlier versions of the S60 UI. This meant that TAT could only add APIs for new features, such as transitions. The disadvantage of this approach is that, in Hampus' view, it means S60 could not take full advantage of TAT's UI technology.

"Where we are able to incorporate Kastor and our other technologies into the core of a platform, developers gain advantages in the way they are able to develop their UI," claims Hampus. "So, in S60 we are effectively skinning the existing UI components. In other implementations - where we don't have similar restrictions - developers get the opportunity to do things such as determine how UI components interact with one another. With the full range of our technology we believe it's possible to design a UI similar to the iPhone in just a few months. However, I do believe S60 has done a very smart job of making the legacy UI look more beautiful."

Another important aspect of Kastor, and one offered in the S60 implementation, is that it makes the definition of the UI's look achievable without heavy engineering effort. "Creating animations and transitions within Kastor has the complexity of Web development," says Hampus. "So it is easily undertaken by graphic designers."

While the integration into the S60 UI may not encompass all of TAT's technology, this does not mean its use need be limited on S60 devices. Hampus points to the Samsung SGH-i450 as an example. The SGH-i450's music player was developed using TAT technology and incorporates an innovative link between a touch wheel (revealed by sliding the phone cover) and a graphical wheel within the player UI. "Our technology allowed Samsung to create a music player that looks and feels totally unique within the S60 world," says Hampus.

TAT's technology is currently implemented in some 200 million devices. "Adding S60 to our client list is very interesting," says Charlotta. "It's a very big part of the smartphone market and an increasingly important platform. In that sense it's important to us, but as we expect to ship in around 10 to 12 percent of all mobile phones shipped this year, it is not a critical part of our business."

However, Hampus sees the creation of the Symbian Foundation as offering TAT significant opportunities to grow its offerings on the S60 platform. "Symbian seems to recognize that an OS is mainly about the plumbing and that differentiation comes from the user interface and services implemented on a device," says Hampus. "We find that pleasurable, because it means our technology is recognized as a key part of the differentiation layer. In the past extending the reach of our technology has been hampered because of the number of platforms it needed to be integrated with. It's much easier for us to work with a platform we know lots of people will use. This means we will be able to add innovation on top of the platform and provide out-of-the box features to manufacturers more quickly and with far less risk. We are very happy that the industry has chosen a platform we are already pre-integrated on."

The S60 UI has however not been short of its critics, both from developer and user communities. "The new UI is quite a change. Had you asked me a year ago if I thought the S60 platform had a long term future, I don't think I would have replied positively," says Hampus. "Yet in the last 12 months I've had 3 different S60 devices and they have been great. I think Nokia has really matured the platform and combined it well with cutting edge industrial design."

Even so, Hampus sees challenges ahead for the S60 UI. "The UI is getting increasingly complex because of the clutter of features. I also wonder if it has gone too far towards a desktop metaphor. I don't think that's the way phones should work," says Hampus. "If you look back at the early camera phones, you took a picture using the select key. These days it's done with a dedicated camera button. Now, if you look at Nokia Maps, it doesn't look at all like S60. I see UIs becoming more tailored to the nature of the application, mimicking how users expect those applications to work."

In addition, developments in the UI will not be restricted solely to its look and feel or navigation. "There is no shortage of new UI technologies: projected UIs, haptics and a range of sensor technologies are all waiting to find an application," says Hampus. "I think the industry will go through a period of experimentation with UI paradigms over the next few years, finding the right way to apply these technologies. However, I see eighty percent of navigation remaining conventional and the new technologies adding smart features." An example Hampus sights is using accelerometers to detect when a phone is on the move and automatically turn up the ring tone volume.

From TAT's perspective this new UI technology landscape is something the Symbian Foundation is well positioned to take advantage of. "With the big five device manufacturers rallying around this platform it is going to be much easier for us, and other UI technology companies, to make significant investments in porting technology to the platform, because we know it will be used," says Hampus. "And whatever new technologies emerge, I see our offerings making all these UIs much more appealing to the user and much easier to use."

Currently the transition and animation effects in S60 3rd Edition, Feature Pack 2 are predefined. Third-party developers and graphic designers are not able to manipulate or define these features.

For more information on TAT visit www.tat.se.