Blog

Voice user interfaces (VUIs) are a type of user interface that allows users to interact with a mobile application using voice commands and natural language. VUIs are becoming more popular and prevalent in mobile applications, as they offer many benefits and advantages over traditional graphical user interfaces (GUIs). However, they also pose some challenges and limitations that need to be considered and addressed. In this blog post, we will explore what VUIs are, how they work, why they are rising, what are some of the examples, benefits, pros, and cons of VUIs in mobile applications, and what are some of the best practices and tips for designing and developing VUIs for mobile applications.

What are VUIs and how do they work?

VUIs are user interfaces that use speech recognition, natural language processing, and speech synthesis technologies to enable users to communicate with a mobile application using voice. VUIs can be either text-based or voice-based, depending on whether the output is displayed as text or spoken as audio. VUIs can also be either standalone or multimodal, depending on whether the input and output are exclusively voice or combined with other modalities, such as touch, gesture, or vision.

Voice user interface VUIs

The basic components of a VUI are:

  • A microphone that captures the user’s voice input
  • A speech recognition engine that converts the voice input into text
  • A natural language understanding engine that analyzes the text and extracts the user’s intent and parameters
  • A dialog manager that manages the conversation flow and logic
  • A natural language generation engine that generates an appropriate response text
  • A speech synthesis engine that converts the response text into voice output
  • A speaker that delivers the voice output to the user

Why are VUIs rising in mobile applications?

VUIs are rising in mobile applications for several reasons, such as:

User convenience: VUIs allow users to interact with a mobile application hands-free and eyes-free, which can be useful in situations where the user is busy, distracted, or impaired. For example, a user can ask for directions while driving, order food while cooking, or check the weather while dressing up.

User experience: VUIs allow users to interact with a mobile application using natural language, which can be more intuitive, expressive, and engaging than using graphical elements, such as buttons, menus, or icons. For example, a user can ask a question using their own words, rather than typing or selecting from predefined options.

User accessibility: VUIs allow users to interact with a mobile application regardless of their literacy level, language proficiency, visual acuity, or motor skills. For example, a user can use voice to access information or services that may otherwise be difficult or impossible to access using GUIs.

Technological advancement: VUIs are becoming more feasible and reliable due to the rapid improvement and innovation of speech recognition, natural language processing, and speech synthesis technologies. These technologies enable VUIs to understand and respond to a wide range of user inputs, accents, contexts, and emotions.

What are some of the examples of VUIs in mobile applications?

There are many examples of mobile applications that use VUIs, either as their primary or secondary interface. Some of the most popular and well-known ones are:

Siri: Siri is a voice-based personal assistant that is integrated with iOS devices. Siri can perform various tasks for the user, such as making calls, sending messages, setting reminders, playing music, searching the web, and more. Siri can also interact with other apps on the device, such as Maps, Calendar, Photos, and more

Voice user interfaces
Voice user interfaces

Alexa: Alexa is a voice-based virtual assistant that is integrated with Amazon devices. Alexa can perform various tasks for the user, such as playing music, controlling smart home devices, ordering products from Amazon, and more. Alexa can also interact with other apps on the device, such as Spotify, Uber, Netflix, and more.

Google Assistant: Google Assistant is a voice-based virtual assistant that is integrated with Android devices. Google Assistant can perform various tasks for the user, such as searching the web, getting directions, translating languages, booking flights, and more. Google Assistant can also interact with other apps on the device, such as Gmail, YouTube, Google Photos, and more.

Voice user interfaces
Voice user interfaces

Cortana: Cortana is a voice-based virtual assistant that is integrated with Windows devices. Cortana can perform various tasks for the user, such as managing calendars, sending emails, setting alarms, checking news, and more. Cortana can also interact with other apps on the device, such as Skype, OneDrive, Office 365, and more.

What are some of the benefits of VUIs in mobile applications?

Some of the benefits of using VUIs in mobile applications are:

  • Faster and easier interaction: VUIs can enable faster and easier interaction between the user and the mobile application, as voice is a natural and efficient way of communication. For example, a user can say “Show me the nearest pizza place” instead of typing or tapping on the screen.
  • Higher user satisfaction and retention: VUIs can increase user satisfaction and retention by providing a more intuitive, expressive, and engaging user experience. For example, a user can feel more connected and satisfied with a mobile application that responds to their voice in a human-like and personalized way.
  • Higher conversions and revenue: VUIs can increase conversions and revenue by providing a more convenient and accessible way of accessing information or services. For example, a user can be more likely to buy a product or service from a mobile application that allows them to use voice to search, compare, or order.

What are some of the pros and cons of VUIs in mobile applications?

Pros:

  1. Voice is a natural and efficient way of communication
  2. Voice can provide hands-free and eyes-free interaction
  3. Voice can provide more intuitive, expressive, and engaging user experience
  4. Voice can provide more convenient and accessible way of accessing information or services
  5. Voice can leverage the advancement and innovation of speech technologies

Cons:

  1. Voice may not be accurate or reliable in noisy or crowded environments
  2. Voice may not be suitable or preferred for private or sensitive information
  3. Voice may not be compatible or consistent with other modalities or platforms
  4. Voice may not be easy or clear to discover or learn
  5. Voice may pose ethical or social issues, such as privacy, security, bias, or trust

What are some of the best practices and tips for designing and developing VUIs for mobile applications?

Designing and developing VUIs for mobile applications is not an easy task, as it requires a different set of skills, principles, and tools than designing and developing GUIs. Some of the best practices and tips for designing and developing VUIs for mobile applications are:

Understand your users:

You should understand your users’ needs, goals, preferences, behaviors, and contexts before designing or developing your VUI. You should conduct user research, such as interviews, surveys, or observations, to gather insights and feedback from your target audience or user persona. You should also test your VUI with real or potential users to validate your assumptions and hypotheses, and to evaluate your usability and performance.

Define your scope and functionality:

You should define your scope and functionality of your VUI based on your user research, your business objectives, and your technical capabilities. You should prioritize the most important or frequent features or functions that you want to offer through voice, and avoid adding unnecessary or complex features or functions that may confuse or frustrate the user. You should also consider how your VUI will integrate or complement with other modalities or platforms that your mobile application supports.

Design for voice:

You should design your VUI for voice, not for text. This means that the content, structure, and tone of the voice input and output should be natural, conversational, and human-like. For example, the voice output should use simple and clear language, avoid jargon and acronyms, use contractions and colloquialisms, and vary the pitch and intonation.

Design for context:

You should design your VUI for context, not for isolation. This means that the voice input and output should take into account the user’s location, situation, goal, and preference. For example, the voice output should provide relevant and personalized information, adapt to the user’s feedback and behavior, and respect the user’s privacy and security.

Design for feedback:

You should design your VUI for feedback, not for silence. This means that the voice input and output should provide clear and timely feedback to the user to indicate the status and progress of the interaction. For example, the voice output should acknowledge and confirm the user’s input, provide error messages and recovery options, and use sounds and cues to signal transitions and actions.

Design for discovery:

You should design your VUI for discovery, not for assumption. This means that the voice input and output should help the user discover and learn about the features and functions of your mobile application. For example, the voice output should provide guidance and instructions, offer suggestions and hints, and support multiple ways of expressing the same intent.

Conclusion

VUIs are a type of user interface that allows users to interact with a mobile application using voice commands and natural language. VUIs are rising in mobile applications, as they offer many benefits, such as user convenience, user experience, user accessibility, and technological advancement. However, they also pose some challenges and limitations that need to be considered and addressed.