The mobile user interface is becoming a key differentiator for mobile telephony devices and services. The increased focus on usable, emotive, and branded user interfaces is the result of three key drivers. (The term "device user interface" refers to both the "core" applications management environment and applications such as contacts, messaging, and call control, as well as third-party applications such as games.) First, standardization of mobile platforms, networks, and screen technology allows the production of more-powerful handsets at lower cost. Such handsets are capable of presenting complex and display-rich user interfaces (see Figure 1) that are more attractive to users and content providers. Second, competition for the loyalty of mobile users is intense. Both mobile operators and manufacturers see a well-designed and emotive user interface as a way to differentiate their otherwise "me-too" products from competitors. Finally, end users are demanding ever more easy-to-use services and devices especially as device/network features, and therefore complexity, increase.
This user-interface design as a commercial imperative has meant that collaboration on the user-interface design has become important to those organizations facing end users, e.g., the operator and manufacturer [13,14]. The increased buying power of operators through transnational mergers, coupled with their desire to push their own brand in all aspects of product use, has created a new commercial environment vis-à-vis the user interface. In this environment, the operator and their handset "vendors" are required to work together in close proximity and within tight timescales.
The first clear example of a new kind of collaborative UI design activity began to take shape in 2003 as Vodafone  began to define its Live! WAP Service following a model that had already been defined by NTTDoCoMo in Japan . At this time, the author led a major manufacturer's first attempts at collaborative UI design across its European portfolio with the top six European operators. Codesign was born.
Who Owns the User Interface Design?
How does this collaborative model change the UI design process? Until recently, the user interface of mobile devices was researched, designed, developed, and tested by UI groups within manufacturers such as Nokia and Motorola. Development took place on proprietary software and hardware platforms. These UI groups most likely resided in the engineering organizations since the UI is seen as essentially another software component to be developed. Here, although often feared as "subjective" or "creative," the UI team is regarded as the owner and architect of UI quality and strategy.
With the codesign model, design control must be shared with other organizations, e.g., operator design teams that are more likely to be in marketing groups or third-party application developers. These teams may be as well or better skilled to produce user interface designs but will have different design and commercial objectives. For example, an operator design team will focus on directing users to ARPU-generating features such as MMS or Video call. (ARPU, average revenue per user, is a common measure of consumer spending on mobile services over a fixed period.) A manufacturer design team will focus on making the most likely task easily accessible regardless of its revenue-generating potential.
Alternative Routes Open to Operators to Codesign the User Interface.
In order to avoid the challenges of working with well-established manufacturers, some operators have chosen to work with ODMs (original design manufacturers) or low brand-equity OEMs (original equipment manufacturers) to ensure closer control over the user-interface design and development, e.g., Orange Group with HTC of Taiwan, Vodafone Group with Huawei of China.
In addition, the selection of devices by operators that use open UI software (Mobile-Linux , JAVA (J2ME) , Symbian  and Flashlite ) and participation in new "hardware agnostic" software development activities gives them and application developers more control over core UI development.
Other Codesign Webs.
The collaboration of operator, manufacturer, and software developer is the first step in the evolution of codesign. A new and more interesting development (from the point of view of experience-focused rather than technology-focused design) is the entrance of MVNO and consumer brands into the design arena.
For example, media group Disney is developing its own mobile products in Japan and Hong Kong. Disney works with a small Chinese ODM to manufacture its product, whose user interface employs UI software customized by Disney. The products are subsequently used to promote the Disney brand and content through the Club Dmobo brand. A UI team within Disney's Internet Division works directly with the manufacturer to produce the DMobo handsets.
A second example is the emergence of mobile virtual network operators (MVNOs). These operators do not own network infrastructure; rather, they piggy-back on an incumbent operator, allowing them to focus on services and brand rather than network management. Though initially offering standard mobile devices and services, MVNOs around the world such as ESPN, AmpdMobile, and Virgin are challenging incumbent operators in terms of brand recognition and service innovation. MVNOs are even looking to develop their own handsets' look and feel by working with lesser-known handset brands from Asia and linking them to well-known content brands. As a recent new article noted:
"Following the recent introduction of new music phone models from Motorola and Nokia, UK-based wireless carrier Virgin Mobile has unveiled the Slider Sonic phonethe first music phone the company has offered to date. Available in October, the £141 (207 euro) Slider Sonic, made by Kyocera Wireless, comes with 32MB of memory (upgradeable to 512MB), a video recorder and digital still camera. The phone will also be embedded with music videos from Seether and Submersed, AOL's AIM software, and links to mobile content from Virgin partners MTV and Comedy Central." [3G News, Dec 2005]
How is codesign developing in different markets? Currently, Europe and Japan  represent the most developed market in the area of codesign. However, established markets such as the US, South Korea, and emerging markets such as China, South America, and Russia are presenting new opportunities and challenges for companies wishing to deliver mobile products and services together.
The development of codesign in a market depends on a number of key factors:
- the market "muscle" of individual operators to negotiate low unit costs with customization included
- the willingness of manufacturers to give up "their" user interface design/brand
- the level of customizability of device software and hardware, i.e., proprietary vs. open OS
- the development processes of manufacturers and operators
- the commercial value operators see in focusing on UI design
- the level of detail of design specifications and strategies developed by operators
A number of mainland Chinese manufacturers are recruiting from psychology and design courses and hiring Western designers.
On close inspection, two key codesign models are apparent. First, the "design-out" model: the codevelopment of products in one market for sale in another. Design requirements come from the buyer in the target market such as Europe. In contrast to this outsourcing model, there is a "design-in" model, in which local companies develop and design for their local markets.
Today, the first model is prevalent. Many western mobile operators are developing their customized handsets in China and Taiwan for use in Europe and the US. The second model is peculiarly fitting for China, where there already is a massive manufacturing base but also an immense and eager user base. In order to develop successful products for their local markets, the manufacturers must greatly augment their research and design capability. If they do this well, they may even be in a position to export to Western markets. A number of mainland Chinese manufacturers are pursing this strategy by recruiting from psychology and design courses and hiring Western designers.
In China, the author is providing design and process consulting to a number of local and Western manufacturers, operators, and design agencies who are collaborating on mobile user interface design projects. The following issues emerge:
- There are over 40 device manufacturers active in the Chinese market.
- Western manufacturers operating in China are seen as insensitive to local operator and user needs and unwilling or unable to devote development resources to these markets.
- Chinese operators find it difficult to collaborate on design with Western companies due to cultural and time differences.
- Price competition is furious between Asian manufacturers; user interface differentiation may be a key way to differentiate.
- The focus of many Chinese manufacturers is currently on lowering inventory due to massive overproduction, rather than innovative design.
- Asian operators are not devoting energy to specifying "their" user interface in sufficient detail to drive manufacturers.
- If Asian manufacturers are to break into the European markets, they must compete not only on price and features but also on their ability to engage in codesign activities. Operators and manufacturers must convince consumers to move to 3G services.
In order to demonstrate a real codesign process, the following case study outlines the key steps, outcomes, barriers, and lessons learnd in a codesign process between two major brands. The X portal was launched by operator Anycom across a small number of handsets from a predominantly low-brand-equity manufacturer. At inception, the customization of product interfaces was limited to visual elements such as color scheme and limited iconography, as well as interactive elements such as bookmarks. Anycom's ability to persuade larger manufacturers to adhere to Anycom design guidelines was limited. However, as the success of the X service became clear, Anycom adopted a "consolidated" purchasing program across multiple countries to increase its buying power and influence. Led by a constantly evolving set of user-interface requirements that increasingly touched on interaction paradigms and layouts, and a growing user interface team, Anycom set about selecting those manufacturers that it felt would be willing to customize their user interfaces to the required level, at a competitive price. Anycom selected both brands well known to subscribers as well as some lesser-known Asian brands.
The Codesign Process.
The first step in the codesign process was that both operator and manufacturer prepared their own design guidelines. On the manufacturer side, descriptions of possible customizations were prepared, i.e., those customizations that could be easily implemented within current cost and timescale limitations. Anycom prepared increasingly elaborate design guidelines touching on low-level generic UI elements, e.g., menus, icons, as well as specific service interactions, e.g., MMS, browser, contacts.
Codesign places particular pressures on those used to working within the boundaries of their own company's design culture.
Once engaged, a manufacturer was required to make as much of its design rationale available to the operator as possible (UI flows, user research, graphic design exploration). Workshops were organized to present early design specifications or more-concrete product specifications, with the operator proposing modifications where necessary.
The Customization of the Mobile User Interface.
The following list highlights key customized elements in the final products:
- Power up and down graphics
- Default screensaver, ring tone, wallpaper
- Preloaded embedded Web links in customized locations in the menu structure
- Many customized icons
- Preloaded Web bookmarks
- Idle screen shortcuts
Interaction and Information Architecture:
- Customized main-menu and second-level structure
- Customized soft-key behaviors
- Color, material, finish
- Logo position on casing
How Did Codesign Change Design Activities?
Within Codesign projects, the design activity became highly collaborative between design teams from different organizations. In addition, the increasingly commercial nature of the UI (and its expression of manufacturer or operator brands) brought marketing and sales influences to bear on what were in the past essentially design decisions.
Barriers to Successful Codesign.
The products resulting from the codesign collaboration showed the early steps in real codesign between two branded companies. Whilst a reasonable level of customization was achieved, a number of key barriers to effective customization were identified.
- Ambiguous carrier-requirement specifications
- Unclear brand relationship between operator and manufacturer
- Conflict between sales and development in terms of customization scope and timelines
- Shifting operator requirements
- Shifting device specifications
- Lack of communication between design teams
- Lack of clear role definition
- Inflexible software and development processes
- Tight development schedules
- Localization needs of operator and internal conflict between local markets
Based on the case study, the following guidelines can be posited:
- Codesign must be collaborative, making the most of both the manufacturer's and operator's design experience rather than one party dictating to the other.
- To compete in future markets, devices should be developed a priori with the maximum flexibility at the UI level. This can take the form of built-in customization features or a decoupling of the user interface from core software development [9, 1].
- Customization should be agreed upon at a project's outset and should be treated as part of the commercial contract with resulting cost, schedule, and deliverables.
- Development tools that can be shared with operators and/or service providers accelerate user-interface iterations and allow clearer communication. Tools should allow control over interaction flows, layouts, and UI elements.
- The relationship between partner brands should be made clear at the project's outset.
- A design management role must be identified to act as liaison between design teams, marketing, and commercial teams. This role should be a user-interface design expert with commercial experience.
The design environment described thus far presents a number of signposts for future mobile UI developments.
The Future of Codesign.
The codesign imperative is changing the way the user interface is specified, designed, and developed, perhaps for the better. Manufacturer design organizations are being forced to adapt their working processes to be more responsive to customers.
User-interface specification and development tools are also being developed to allow easier design collaboration. These tools will benefit all design teams and application developers. Ultimately such tools, when coupled with open operating systems [1, 6], will decouple core UI design activities from device manufactures. Codesign will then be between core application/toolkit developers, service providers, and operators much as it is currently in the mobile games development market .
Innovation or Conformity.
The desire of international operators to offer a consistent UI across all the device brands that they propose may reduce the natural innovation and richness within the user interface that is seen in the current marketplace.
Consistency between manufacturers in the basic elements of the user interface (fields, buttons, help information, navigation cues) is possible and necessary . User-interface differentiation should be promoted for higher-level core activities such as service discovery, content presentation, navigation and file management, location-based services, and dynamic interactions.
The Evolution of Mobile UI Designer Roles.
Codesign blurs boundaries between traditional design competencies. Innovation within core areas such as the relationship between software and hardware remains a key strength of manufacturers. However, as the software of mobile devices becomes increasingly detached from proprietary hardware platforms, design control will shift further into application, operator, content, and brand domainsit may well be here that mobile user-interface designers will find their future. For those designers who remain in manufacturer organizations, codesign places particular pressures on those used to working within the boundaries of their own company's design culture. The role of these designers must become more akin to that of a consultancy company, where close customer relationships are essential.
Brand Is King.
As the cost of mobile devices falls, basic UI function becomes commoditised, and flexible content platforms gain popularity, consumer brands will begin to offer their own MVNOs and branded devices/services. Examples of brands already making early attempts are Armani, Gucci, B&O, Disney, and Tiffany. Consumer brands are firmly rooted in people's lifestyles in a way that mobile operators and manufacturers are not. Consequently, they may encourage users to capitalize on 3G network and device capabilities where operator strategies have failed. From a codesign point of view, design activity will not be on the level of interaction design but rather on the portrayal of content, lifestyle, and brand.
The Rise and Rise of Asian Manufacturers.
As discussed earlier, the easiest route to massive UI customization is for an operator to work with OEM or ODM manufacturers who will dedicate resources to operators' needs. The majority of such manufacturers reside in Far-East Asian markets. Developments in codesign have therefore brought a number of previously unknown manufacturers into the hands of Western users, providing greater choice and promoting earlier adoption of advanced features that are prevalent in Asian markets.
Thanks to this exposure to new markets, ODMs and OEMs are learning that their brand and UI are important and are placing increasing resources in this area. Perhaps in time they will compete with their more established Western rivals in local and overseas markets.
9. Jacob Eisenstein, Jean Vanderdonckt and Angel Puerta "Applying Model-Based Techniques to the Development of UIs for Mobile Computers," Proceeding of the 6th International Conference on Intelligent User Interfaces, 2001
David M. L. Williams
Asentio Design Ltd.
About the Author
David Williams, PhD, is a managing partner of Asentio Design in Shanghai, China. Prior, David led international projects in user interface design, strategy, and user research for companies such as Motorola and Razorfish, major European telecoms such as Vodafone and Orange, and European Commission projects (IST, ETSI). David has also worked with Korean and Japanese manufacturers to deliver product user interfaces that meet European user needs. Widely published, David is also active on a number of international conference technical committees such as BCS Mobile HCI and IEE Mobility.
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