Au says the collaboration between designers and engineers is healthy. A lot of the design team's time is spent on setting standards and building a style guide for engineers to ensure a project will really end up looking like a Google product.

"Rather than having 30 different styles of tabs, we just choose one or two," Au says, "and they're the canonical types that have been proven to work. Then we create a toolkit for the developers, so that for basic interactions, where the patterns are pretty known and common, they'll have reusable components. Then at least they can get 70 to 80 per cent of the way there without having a designer involved."

Google has always had the mantra of 'focus on the user and all else will follow', so the company puts a significant amount of effort into researching its users. In fact, Au estimates that 30 to 40 per cent of her 200-strong worldwide user experience team is compromised of user researchers.

"Data can be invigorating when you understand the 'why' behind the 'what'," she explains. "For example, we work with vision scientists to understand how people process information, so we can create better predictive models for what will work.

"We also use a variety of methods, whether it's quantitative analysis, data mining or surveys, and do quite a bit of ethnographic work, too. While it's easy to design for people like yourself, it's hard to design for people in a totally different environment, so we've done field studies and rapid prototyping to better understand what their needs are and how they're using the internet."

On the move

One outcome of these studies is Google SMS, a suite of mobile apps that enable people to access information via SMS on topics including health, agriculture tips and local weather. The first country to receive the new service is Uganda, with other areas in Africa, where mobile phones are more common than PCs and only have voice and SMS capabilities, to follow.

"When we were prototyping and simulating this SMS-based search service, we had to understand what kind of information people were looking for," Au explains, "because we couldn't really scour the world's information and make it all available via SMS."

The suite also includes Google Trader, a marketplace for any type of product or service, and Google SMS Tips, a question-and-answer tool that interprets search queries, specifically on health and farming issues, and uses a database to return the most relevant answers via SMS.

Creating a coherent design experience

Au's design team is also spending a lot of energy on trying to create a coherent design experience. Projects are usually initiated by engineers and designers join in later. This traditionally bottom-up culture can make it difficult, but having more consistency across Google is crucial to build better products and a stronger brand.

"There's already a lot of consistency across Google's search products but there isn't much of a relationship between that and a lot of our apps. Many were Google branded and designed after we acquired companies like GrandCentral – so I spend most of my time right now figuring out how to apply the principles behind Google's design that made Google Search successful to all other products."

As part of this, Google recently rolled out new logos for all products, featuring a more standardised typeface and layout. The redesign of Google Reader last December was the first project to feature square corners and calmer colours. The changes addressed latency issues, while tying the service back to the brand.

When Google Voice (formerly called GrandCentral) launched a few months later, it looked similar to Reader. "This was a very deliberate choice because, as we start rolling out more redesigns and incremental improvements for our products, the look and feel for these products will begin to converge. We're also working to tie together the mobile experiences on smart phones, so they have a more coherent feel to them and relate better to the desktop experiences."

Google's approach to design will continue to divide opinion, but there's no doubt its refreshingly clean and simple homepage has served the company well. And so, as Google branches out beyond search, its design decisions will become more important than ever.

Using a fascinating arsenal of research, user testing and analytics tools, Google has turned this process into a science.

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First published in .net Issue 193

Liked this? Then check out Marissa Mayer on the future of Google

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