Bringing Voice to Life: Implementing Voice-Driven Interfaces in iOS Applications

Voice Interfaces in these past couple of years have been a trailblazing achievement for the world of technology. Regarding interaction with different devices and apps, VUI has been a revolutionary achievement. Voice commands are now the new hands-on experience since not much effort is required to look up information or accomplish a certain task. 

Still, on the rising curve, the design of voice UI is an interesting concept in the UI/UX industry. Massive efforts are being made to implement the voice-user interface in iOS app development. User Interface experts around the world are constantly making efforts to ameliorate the VUI technology utilized around the world to simplify the cyclical and repetitive tasks of the world. 

Voice Interface- An Overview

Voice Interface or voice user interface(VUI) allows users to communicate with different devices such as smartphones, computers, digital assistants, etc., via spoken commands and instructions. It makes use of speech recognition to contemplate the user’s voice and reacts to it with simulated speech or other audio cues. 

Due to their inherent nature to constantly evolve, voice interfaces have become trendy in the world of tech. Their algorithms are programmed in such a way that every interaction with them feels human-like or close to it. This familiarity has made the world adapt to famous devices such as Google Assistant, Siri, and Alexa along with the calibration of voice interfaces in multiple mobile apps, smart devices, and cars. 

Due to the constant advancements in speech recognition and natural language processing devices, the responsiveness and precision of these voice assistants have significantly increased which has made them all the more mobile-friendly and reliable. As a result, human-computer interaction keeps on evolving with the help of voice interfaces. 

Elements that make Voice Interface

When it comes to voice user interfaces, speech recognition is considered to be the most vital aspect of it. Besides this, there are several other elements that incorporate a functioning and reliable voice user interface to offer a seamless user experience design. 

The signs of a good voice user interface would not just include functioning automatic speech recognition, but also other aspects of the feature such as being able to synthesize natural conversation, recognize spoken instructions, as well as deliver messages properly. Some of the most important elements of the voice user interface are given below:

1. Speech recognition

The most important feature of the voice interface is its capability to understand the human voice. There are specialized tools and advanced programming that help in managing voice recognition. 

The bottom line is for the interface to recognize the user’s voice as well as choose a voice command to respond. 

2. Natural Language Processing (NLP)

Natural Language Processing improves the capabilities of voice recognition. NLP makes use of machine learning as well as artificial intelligence to understand the voice commands and human language it encounters.

This speech interface ability allows the product or service to have a much clearer understanding of the natural human vernacular, the way we speak in our daily lives.

3.  Speech Synthesis

Once the machine can understand human speech, the problem arises as to utilizing what voice it will interact with. The machine needs to synthesize voice commands to do that. This is exactly where a step-by-step analysis of the spoken language should take place.

Since communication needs to be a two-way street between the human and the machine, speech must be synthesized by voice interface to provide a response based on the human’s need.

4. Feedback

Through feedback, there is a smooth dialogue flow between the machine and the human. The voice interface understands the humans’ command, synthesizes the spoken language, and then accordingly issues a response that completes the primary interactive loop between the two parties. 

Speed also becomes a certain factor when it comes to the efficiency of the voice interface to provide feedback to the users. 

Challenges to overcome while designing VUI

Designing a perfect VUI is something unheard of as there are so many complex queries it has to figure out. However close to perfection, there are multiple challenges a programmer faces while developing a VUI for an iPhone app development company. Below are a few of them that iOS developers generally overlook or are distracted by the more prevailing issues in the meantime:

Privacy and Security

With the integration of voice assistants into our daily lives, concerns surrounding privacy and security have come to the forefront. These digital assistants, while incredibly helpful, can raise valid worries about the confidentiality of personal information.

In the past, certain voice assistants, like Alexa, stored all user interactions, posing a potential risk for information leakage. Unfortunately, there have been instances where private data found its way into the wrong hands, understandably eroding trust in voice AI technology. However, newer voice assistants have taken steps to address this issue by automatically deleting previous conversations within 24 hours. It’s worth noting that enhanced security measures are not limited to voice assistants alone; mobile app security is equally crucial in safeguarding user data. The evolving landscape of voice technology and mobile app security demands ongoing vigilance to ensure user privacy remains a top priority.

Express what voice assistants cannot perform

No matter how close to reality a voice artificial intelligence (AI) may get, there are always shortcomings of such technology in general. One such limitation is if you ask the AI to set a meeting for 4 p.m. and then want to change it.

The AI would respond ‘I am not sure what you said, would you like me to set up a meeting for 4 PM?’ To avoid providing such a gnarly user experience, the response should be ‘Sorry I am still working on scheduling a meeting for you.

Issues in Prototyping and Testing

Voice UI prototyping and testing is another one of these problems. Prototyping allows you to examine things when the developers try to test the product. The developer has set a certain feature that the user can shop for groceries through the voice AI. 

The tricky part is that the user can say the same thing in various ways and different styles which can be a complicated thing to keep track of. As a result, it becomes more and more difficult to test the prototype on questions like these if they aren’t developed efficiently with the help of voice search technology.

Language Support

The most fundamental thing in a voice AI is that it must understand the language of the user. Not only that, but it must also respond in the same language. Unfortunately, there are many languages that AI cannot comprehend as of yet. Adding other languages, dialects, and accents is still a work in progress. 

Steps to Design Voice User Interface

1. Select your target audience

The first step in designing VUI includes deploying the user-first design just like in any other digital product. The focus here is to gather information and cogitate on the audience’s basic needs and requirements which sets up the foundation for the VUI. 

You need to identify the users’ desires and pain points of their experience. This will help you in recognizing the areas where the users will benefit. Collecting information on the user’s language is a given- the way they talk and how they phrase their sentences. This provides you versatility in speech and the interface would cater to a multitude of vernacular.

2. Establish the capabilities

In this stage, you need to outline the interface’s capabilities and shape the product. Some of these capabilities include:

• Simulate the scenarios of interaction with the product- These scenarios are precursors to the app ideas and must be spotted to transform them into conversational dialogue flow. These scenarios help in making the developers understand why someone would need a VUI. Hence, these scenarios must be designed keeping in mind the needs and wants of the users. At times, it can be difficult to determine the scenarios that are worth analyzing and ignore the ones that are not so important. 
• Ensure that these scenarios are voice activated- The purpose of these scenarios is to make sure that the users can deal with the problem more efficiently than they would with the alternatives. This step’s purpose is to find the specific and esoteric cases that are advantageous to the user.
• Some instances of these cases would be when users cannot access the visual interface as they are busy doing something or when they want to do something swift such as play music which takes less effort.

Three factors- Intent, Utterance, Slot

Intent- This implies the bigger picture that the product is supposed to depict and see. The intent is of two kinds- High utility (fairly accurate and straightforward command such as ‘turn the lights on in the living room’) and Low Utility (varied and more difficult to decrypt) 

Utterance- It implies the multiple ways in which a request can be phrased or put up. For instance- Instead of saying ‘Play any song’ the user commands ‘I want to hear some music’ or even ‘Can you play a song’ and so on. As a result, all the designers need to make sure that they consider different possibilities of phrases and their variations.

Slots- The slots come into play when the intent is not enough. Once the command is given and the response is in progress, they also refer to additional information and resources to provide the best results possible for the user. These resources can be optional as well as required. For music, the genre was not described hence it would be optional. However, if the query was to book a cab, the slot would come into action as a ‘destination’.

3. Build A Prototype

The flow of the dialogue determines the answer to ‘How to create a smooth voice interaction between the user and machine?’ For every requirement that you are targeting your product needs to have a smooth and human-like dialogue which is where developers need to start.

The developer needs to pre-meditate a lot where the dialogue can go as the interaction progresses forward. Some of the things to account for are the main keywords for communication, different branches where the conversation can head off, and template dialogues for both users and assistants. 

There are multiple prototyping tools available at your expense for VUI design. Some of these tools are Sayspring, Google’s SDK, and Amazon Alexa Skill Builder. Below are some of the aspects you need to consider while building a prototype VUI.

a) Writing Dialogues

A compilation of dialogues is the cobblestone through which the voice user interface flows seamlessly. Below are a few ways in which you can develop interactive dialogue:

• Try to simplify the arduous process by keeping the number of steps to a minimum.
• Don’t teach commands to users as that should happen in a natural way. As opposed to that, make your VUI more interactive.
• Make sure to keep the questions and responses short and simple. Some of the instances are given below

b) Spot Errors

It is better to find any errors or bugs in the system during the interactive process than post-release when the errors become undeniably complex to fix. Below are a few things you should consider steering clear of and keep in perspective to eliminate any interactive errors:

• Lexical Ambiguity- Words can mean several things at a time. This means that if a person uses the word ‘Good’ it can mean ‘okay’ which is a much more moderate version. Hence, ensure that your voice assistant can differentiate between the nuances of words.

• Pronunciation errors- This one is a classic as different dialects, accents, and qualities of voice can pronounce words differently. The user can get frustrated easily if the intent of his/her query is confusing to the VUI due to accent or dialect barriers. The assistant must be able to bridge the gap between speech obscurity and real words to respond accurately and efficiently.

• Not any accurate options- Make sure that users get the worth of their money and acquire relevant and credible information from the interaction. You don’t want the user to paraphrase the query incessantly until the assistant provides him/her with a credible answer. 

Regardless of the accuracy of the result, the assistant must always respond to a query put forward. For instance, if the user asks to find any hotels around him on a shoestring budget, even if the assistant is unable to do so, it should reply with “I couldn’t find any hotels around you. Would you like to raise your budget or let me find a place a little further?’

c) Display your brand’s vision

The tone of the voice matters a lot even in a human conversation. Your dialogues become the nature of your product which should always have a positive impact on the user. Dialogues must be said not for the sake of interaction but to satisfy the user’s needs.

d) Utilize existing content

Utilizing the available data can immensely customize things for the user. This data is strictly based on all the conversations your product has with the user. For instance, let’s take an OTT scenario ‘Stream a show from Netflix’ The system should reply ‘Would you like to continue the last show you were watching?’

4. Test Your Product

Once everything is in order, it is time to analyze and examine the product and witness the fruit of your labor. There needs to be quality testing of your VUI to see if it fulfills all the necessary criteria to be benchmarked as a high-quality VUI. You can test your prototype in two ways:

• With test simulators

There are multiple tests utilized in mobile app development that can aid you in reviewing your final product. These tools are also provided by famous companies such as Google and Amazon. Alexa Skill and Google Action of the product are utilized for application testing considering the hardware devices and their settings.

• With target users

You can organize groups of your targeted audience and eventually incorporate testing sessions to notice how users interact with your product. This also allows you to track task completion rate as well as customer satisfaction score (CSAT).

5. Improve

You can review your product more deeply once it hits the market. You will be able to view different UX insights. This step of the process allows you to analyze how users interact with your product. The metrics and criteria you are supposed to evaluate are given below:

• Languages Utilized
• User engagement metrics
• Messages per session along with the users per session
• Intents and utterances
• Behavior flows

Conclusion

Since VUI is one of the latest trends in technology, it is here to stay and will be optimized and incorporated into multiple products in the future. Although the VUI design interface for iOS apps can be quite a complicated and sophisticated process to complete and is a work in progress, it is still being implemented in many parts of the world. 

Implementing VUI in iOS apps is a great way to simplify daily tasks around the user. It is still a raw aspect of technology, however, there will be many advancements in VUI research in 2023. Combining voice and visuals is something that could positively impact VUIs. They cancel out each other’s drawbacks. This allows VUIs to accomplish complex tasks with realistic voice commands that interfaces are lacking at this moment.