How to Design for Voice User Interfaces

Category: Tech & Innovation
20 Jun 2019
Read time: 3 MIN
The advent of voice assistants like Amazon Alexa has brought about a brand new discipline for brands, designers and marketers to get acquainted with.
Written By
MOF Team
MOF Team

Designing a voice user experience is not the same as designing for a traditional UI. If you want to create an outstanding customer experience, you need to master the practice with an intuitive, natural and effective voice user-interface.

We headed to the UX Crunch Meets Amazon – Designing For Alexa conference to hear from experts in the field on best practices for the design of VUIs and how to maximise usability.

Alright, we’re listening...

“Prepare to fail, and when you do, fail gracefully.” Ben Sauer, director of Conversational Design at Babylon Health.

The speakers at the event were keen to highlight just how complex designing for voice is.

As we’re very much still in the discovery phase of this technology, mistakes are the only way to learn. As the old mantra goes, move fast and break stuff.

Voice design supremo Ben Sauer, who has worked with huge organisations from NASA to the BBC, says there are three core elements to integrating ‘voice’ into anything:

It should make things easier.
It should be faster.
It should feel natural.

In other words – if it doesn’t add value to your offering, don’t bother.


The current state of play

Alexa is now supported by over 30,000 different products, from light bulbs to fridges, televisions to speakers. But she’s not just confined to our homes – you can find her in portable devices like headphones, cars and Fitbits.

Despite this rapid development, many reports suggest that the technology is still frustrating for many.

Rob Farnell, Director of Voice and AI at the BBC, points out, “We’re not designing for our generation. Voice UI is for generations to come, and those of us interacting with it now are merely guinea pigs. When will we completely trust voice? It doesn’t really matter – children are already ensconced – so whether we like it or not simply doesn’t matter.”

So let’s look at the stats. According to research carried out by OC & C Strategy Consultants looking into US and UK markets:

  • 1 in 2 smartphone users use voice technology on their phones
  • 41% of people using voice search have only started in the last 6 months
  • Voice search will exceed 50% of all searches by 2021
  • Smart speaker adoption is increasing, with sales growth up by 137% from Q3 of 2017 to Q3 of 2018

So it’s clear that we need to sharpen up our voice skills.


Designing Alexa Skills – Best Practices

Andrea Muttoni, Senior Solution Architect for Amazon Alexa, outlined some best practices for designing for voice:

  • Use a wide top-level UI as opposed to the more traditional nest style
  • Every interaction should have its own ‘card’. (A card refers to each interaction – every product or journey should have its own card and if someone moves onto a new product or service, this should take place on its own card.)
  • Put actionable info at the end of the message
  • Read out what you’ve written
  • Make it bite-size
  • Include an instant benefit
  • Summarise what the product will provide to the customer
  • Offer different products each time for variety
  • Make the customer aware of any quantity or time limits on the product
  • Offer relevant products to the customer….
  • ….But don’t immediately upsell
  • One breath test – you should be able to say the whole sentence in one breath
  • End with an explicit confirmation (Yes/No) statement
  • Learn and optimise

Other challenges we face in voice search include personalisation – how to accurately deliver the most relevant product or topic to direct the user to next, and how to avoid coming across too sales-y.

As the BBC’s Rob Farnell pointed out: “Once you lose trust, it’s especially hard to get back – particularly in the voice environment.”

Despite scepticism, there is no question as to which way the industry is moving. The fact that global businesses are increasingly investing in the technology, and further results from OC&C’s 2019 study highlight this:

  • Three tech behemoths lead the virtual assistant AI space in the US – Amazon's Echo has 10% penetration of US homes; Google's Home, 4%, and Microsoft's Cortana, 2%.
  • Apple has been left behind. Siri lacks the AI capabilities of Google, while its HomePod has only just hit the market
  • Only 39% of consumers trust in the "personalised" product selection of smart speaker
  • Smart speaker owners skew younger and more affluent, and are more likely to have children
  • Voice purchases tend to be standalone, lower value items
  • The three most commonly shopped categories through voice are commoditised: grocery (20%), entertainment (19%) and electronics (17%). Clothing is fourth at 8%


So, where is VUI heading?

Listen up: VUI is not a stand-alone proposition. It will increasingly become integrated into multi-dimensional experiences and users should be able to seamlessly move from one experience to another.

As with any new technology or marketing channel, the quality of output will improve as brands and businesses learn from the data. Currently, some still think of it as a novelty, but those who see the potential and take it seriously will succeed if they focus on enhanced user experiences rather than gimmicky tactics.


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MOF Team

Published by MOF Team

We are a London-based Brand & Experience Design Agency delivering second-to-none experiences for forward-thinking luxury brands with something to say.