UX Audit: Improving Domino's delivery experience

by
Elisey Kolev

UX Audit: Improving Domino's delivery experience

by
Elisey Kolev

Case Study Overview

Food consumption and shopping behaviour shifted massively because of COVID-19. With restaurants staying closed and households growing weary of home cooking, individuals started turning to takeout.

The global online food delivery industry is expected to grow from $82 billion to $200 billion by 2025. To withstand the competition and keep up with every-changing customer demands, food delivery owners should mind the latest trends and technological advancements.

Domino's is one of the leading brads in popularising food delivery and has taken the strategy to go it alone when it comes to delivering their pizzas, avoiding food delivery operators and relying on their employees. We thought this was a great chance to approach their mobile app and explore how we can improve the experience, leading to increased user efficiency and higher revenues.

What is a Heuristic Analysis?

Heuristic analysis involves having a small set of evaluators examine the product interface and judge its compliance with recognised usability principles (the ‘heuristics’). — Jakob Nielsen, The Nielsen Norman Group

Evaluation criteria for this case study

The 10 Usability Heuristics for User Interface Design by The Nielsen Norman Group was used as the 10 defining evaluation criteria.

  1. Visibility of system status
    The system should always keep users informed about what is going on, through appropriate feedback within reasonable time.
  2. Match between system and the real world
    The system should speak the users’ language, with words, phrases and concepts familiar to the user, rather than system-oriented terms. Follow real-world conventions, making information appear in a natural and logical order.
  3. User control and freedom
    Users often choose system functions by mistake and will need a clearly marked “emergency exit” to leave the unwanted state without having to go through an extended dialogue. Support undo and redo.
  4. Consistency and standards
    Users should not have to wonder whether different words, situations, or actions mean the same thing.
  5. Error prevention
    Even better than good error messages is a careful design which prevents a problem from occurring in the first place. Either eliminate error-prone conditions or check for them and present users with a confirmation option before they commit to the action.
  6. Recognition rather than recall
    Minimize the user’s memory load by making objects, actions, and options visible. The user should not have to remember information from one part of the dialogue to another. Instructions for use of the system should be visible or easily retrievable whenever appropriate.
  7. Flexibility and efficiency of use
    Accelerators — unseen by the novice user — may often speed up the interaction for the expert user such that the system can cater to both inexperienced and experienced users. Allow users to tailor frequent actions.
  8. Aesthetic and minimalist design
    Dialogues should not contain information which is irrelevant or rarely needed. Every extra unit of information in a dialogue competes with the relevant units of information and diminishes their relative visibility.
  9. Help users recognize, diagnose, and recover from errors
    Error messages should be expressed in plain language (no codes), precisely indicate the problem, and constructively suggest a solution.
  10. Help and documentation
    Even though it is better if the system can be used without documentation, it may be necessary to provide help and documentation. Any such information should be easy to search, focused on the user’s task, list concrete steps to be carried out, and not be too large.

Metric system for this case study

Each of the 10 evaluation criteria has been assigned 3 usability rules that support and drive the specific outcome for the heuristic (this number is not set, it can vary). The compliance to each of the usability rules are measured against 4 severity criteria as illustrated in the table below:

Case study metric system

Evaluation for the “Domino’s Pizza Bulgaria” App

1. Is the user aware of their current position within the user journey?

The bottom navigation, combined with the page heading ensure that the user is aware of their current position within the user journey.

Bottom navigation
Page Heading

2. Is there appropriate system feedback to show the corresponding result when a user performs an action?

Issue 1: When adding an item to the shopping basket, a notification with the new total order price appears, but shortly after that it switches to the number of items. This inconsistency might cause users confusion.

Adding item to basket system feedback is not consistent

Issue 2: When menu items are added to the shopping basket there is no system feedback indicating the added quantity for each item. Users might forget if they accidentally clicked “Select” one or two times while browsing the menu and have to open the shopping basket just to check the quantity again.

Menu items added to basket are missing the quantity indication

3. Is the user presented with a progress indicator when actions take more time to get executed?

For the bigger part of the user experience there are no system delays or waiting time. The tracking of an active delivery includes a progress indicator.

1. Are the UI elements and interaction prompts easily recognisable?

The main product services are easy to access and use, which includes choosing a delivery method, adding menu items to basket, checking out and tracking your delivery.

2. Does the online experience replicate the familiarity of offline or previous digital actions and behaviour?

Issue 1: The main navigation and page behaviour could be improved further to resemble the purchasing experience in a physical store. For example the shopping basket and delivery tracker are always visible in the main navigation but disabled or empty by default. Their behaviour can be enhanced to prime the user to explore and purchase more products.

Disabled and empty pages not providing value to users

Issue 2: Browsing through the product’s menu and ordering a pizza doesn’t give the same great feeling associated with the brand’s success, customer experience and physical product’s high quality. Showcasing more of the Domino’s brand personality will create an emotional association in the mind of the customers and increase user retention.

3. Does the product make use of acronyms, technical terms or jargon that need an explanation?

The product uses language, closely associated with online food delivery and the content is simple and easily understandable.

1. Is the user able to exit all states such as pop-ups, or go back to previous stages of the user journey? Is the exit (or return) state consistent and clear?

All pages have a back button, allowing users to return to previous stages of the journey. All pop-ups include a cancel button, however their layout and consistency could be improved to increase ease of use.

The layout and consistency of popups could be improved to increase ease of use

2. Are different user flows supported? Is the user able to use the core sections of the product without signing up?

Issue 1: The user is forced to create an account and follow the predefined user flow which always requires input for the delivery method, address and time, and only then allows users to browse the menu and add items to basket. Giving more freedom to users would account for their usage preference and improve user satisfaction.

Issue 2: After a menu item is added to basket, the only way to change the added quantity or to remove it is from the basket. Adding this option in the menu itself would save users time and increase ease of use.

Issue 3: Currently it’s impossible to order without creating an account. Before logging in, users have the option to browse through the menu, but are unable to add items to the basket or order as a guest.

3. Does the user have control over their personal information?

Issue 1: Users can update their personal information, however, the interaction of editing their profile could be improved to increase ease of use. The option to delete a user’s profile is missing.

1. Is there a consistent internal visual design standard for all interface elements?

Issue 1: There is no internal visual standard for CTAs. Their position, size, text style, shape and background colour are incosistent.

The CTA position, size and style are incosistent

Issue 2: The product uses the visual style of default system elements (components, buttons, pop-ups, fields, map, fonts and more). The UI design doesn’t show the unique personality and style that the Domino’s brand is famous for.

2. Is there a consistent internal interaction design standard for all interface elements?


Issue 1: There is no internal interaction standard for CTAs. Buttons with the same style and expected behaviour interact differently — opening a new page, showing a pop-up or expanding additional input field. This adds uncertainty and makes it difficult for users to build behaviour habits within the product.

Issue 2: The buttons “Register” / “Log in” before login are in the same position and style as the “Choose a delivery method” options after log in. This is not a logical and consistent experience and might mislead users to think they are seeing the same “Register” / “Log in” buttons even after being logged in.

The position of login/signup and delivery options might mislead users

3. Is the product following established external UI conventions?

Issue 1: Most of the product CTAs are very small in size, making it difficult to tap on them. That results in frustration and might lead to reduced ease of use. For example, Apple says that CTAs in mobile UI should be at least 44Х44 pixels, while Microsoft recommends 34Х26 pixels.

Issue 2: Labels are placed inside the actual field entry, having them just disappear once the user starts typing. This interaction adds more cognitive load and puts too much on the user’s short term memory. Labels must offer guidance to users and aim to leave no room for interpretation in the entry fields. When it comes to the labels and placeholders in your app, they still need to abide by the general guidelines of form design: they need to be helpful, precise and objective.

The field entry labels disappear once the user starts typing

Issue 3: Combining the delivery details, shopping cart, recommendations, additional options and payment details in one mobile page leads to a long scroll, frustration and shopping cart abandonment. When they’re ready to buy, users shouldn’t be burdened with complicated and hard to understand lengthy checkouts. Instead, they need a laser-focused user experience that helps them do what they came to do. A progress indicator is especially important for visitors on-the-go who are looking to checkout quickly. A feature like this often makes the process less overwhelming as it can both identify how far long the customer is in the process as well as how much further they still need to go.

Lengthy and hard to understand checkouts lead to frustration and shopping cart abandonment


1. Are there issues that might cause severe damage?

Issue 1: The checkout flow doesn’t give users a simplified and easy to understand review of their order and delivery details. This missed opportunity combined with the lengthy basket page and button label “Complete order” leads to uncertainty and hesitation. As a result of this users might waste time going back to check if they added the right products to cart, if their delivery address is correct, or even worse abandon their purchase.

2. Are there issues that might cause simple annoyances and frustrations?

Issue 1: The button “Complete order” is always active, even when users haven’t chosen a payment method, which is a required field. As a result of this users try to click on the button and are shown an error message telling them to select a payment method first. This annoyance could be avoided by disabling the complete order button and showing a tooltip that guides the users to provide the required details.

The error message related to the payment method could be easily avoided

Issue 2: The contactless delivery option in the checkout flow provides the information in a very inefficient way, putting too much on the user to read, understand, accept and follow the instructions. Improving this experience would better show the brand’s care for their customers’ wellbeing and increase user satisfaction.

Providing a more accessible and easy to understand instructions would improve user satisfaction

Issue 3: Adding a new address is challenging. The interaction with the map makes finding and selecting your address difficult. The map loads a worldwide map view by default, instead of showing an area more relevant to the user’s context. When users interact with the map the location marker is automatically moved in a very unintuitive way. The manual location input field is in the top part of the screen, making it harder to reach and use on a mobile device.

The map interaction makes finding and selecting your location difficult

Issue 4: Updating an existing location behaves different than adding a new location. Users are presented with a new screen, containing 12 different input fields and no map preview, making the interaction significantly slower and hard to use.

The interaction of updating an existing location is significantly slower and hard to use

3. Is there a way for users to catch a mistake and undo before it becomes permanent?

Issue 1: Input fields and forms in the product don’t have any validation or constraints. This lets users make unnecessary mistakes or submit invalid inputs. For example users can input random text in the email field, or input text in the phone number field. Form validation is the process used by form dialogs to alert users of errors in their submissions.

1. Are users expected to retrieve information or previous actions from memory?

Issue 1: It’s impossible for users to access their order history.

Issue 2: Users have no access to their order details while waiting for the delivery to arrive. They can track the delivery status but have to recall the ordered products.

2. Are the interface functions and information visible and easily accessible, thus reducing cognitive load?

The menu provides details about each product, items added to basket are easy to access, and during checkout users can see all relevant and important information. However as mentioned above the checkout interaction could be greatly improved to reduce the cognitive load.

3. Is the user presented with customised content based on their previous actions?

Issue 1: During checkout users receive recommendations to add additional products from the menu, but the suggestions are not tailored to their shopping cart or previous behaviour.

1. Is the user able to customise commonly performed actions?

Users can choose from their pre-saved addresses and payment details, instead of adding them from scratch every time.

2. Is the user presented with shortcuts to end goals?

Issue 1: Users are not given the option to reorder from their history.

Issue 2: Users are not given the option to add products to their favourites, which would make them easier to access.

3. Is the functionality structured in an open-ended rather than a prescriptive way?

Issue 1: Users are forced to follow a predefined user journey and don’t have freedom to interact with the product in a more open-ended way.

1. Is the user interface design simple and easy to understand?

The functionality is not complex, making the design simple and easy to understand. However the content will be easier to read and understand with a better use of colours, text style and white space.

2. Is the user clear on what all the icons mean and why they’re included in the design?

The visual combination of a graphic element and label or description makes the icons clear and understandable. However aesthetically their design and consistency could be improved further.

3. Are the content (text, graphics, photos) and functionality (UI components, layout) supporting the primary goals of users or company?

Issue 1: Products in the menu could be presented in a more attention-grabbing way, by improving the quality and layout of the photos and structure of the product name and description.

The quality and layout of the menu could drive users to purchase more products

Issue 2: Different features overload the basket screen. A more minimalist design without unnecessary elements that could disrupt the user experience would reduce the cart abandonment rates. Reduce on-screen content by redistributing functionality.

1. Is the user presented with error messages (as opposed to no message) when adding incorrect information in a form component?

Issue 1: The product’s forms don’t include error validation. For example when a user provides invalid input for an invoice during checkout there is no error message. The invalid invoice details are accepted and added to the invoice section.

2. Is the user presented with human-readable error messages that offer a shortcut or useful information on how to overcome the problem?

Issue 1: When trying to add an invalid discount coupon during checkout users are not presented with an error message telling them why the input was not accepted.

Invalid discount coupons are rejected without providing any error message or instructions

3. Is the user presented with polite error messages that don’t blame the user for the error?

Issue 1: The error messages in the product are simple and easy to understand but don’t provide any positive feedback or support. For example when trying to add a sold out product to the shopping basket, users are presented with a generic error message.

Error messages could provide a more positive feedback and help the user to solve the problem or engage with the product more efficiently

1. Is the user presented with contextual help and instructions on how to use the product’s services?

There is no need to onboard users to the product, because the experience is simple and straightforward. However as mentioned above usability could be improved to increase ease of use.

2. Does the user have access to documentation with relevant topics to help reach their goal?

Issue 1: There is no F.A.Q. section or help area for users to find more information.

3. Is the user presented with other channels of communication to receive assistance to reach their goal?

Issue 1: There is no support channel or contact form for users to receive additional assistance.

“Domino’s Pizza Bulgaria” Heuristics Analysis report

From the level of compliance for the usability rules, a score is allocated for each of the 10 heuristics. Drawing up a radar chart is an excellent way to get an overview of the areas in which the product is lacking.


Domino’s Bulgaria mobile experience scored by the evaluation criteria

Radar chart overview of the usability analysis

Improvements Comparison

Current mobile experience

Improved layout after the usability analysis

Summary

Delivering a seamless user experience is key to attracting and retaining users on your app. Conducting a Heuristic Analysis is a great way to get an objective view of a product’s usability status and uncover potential opportunities for improvement. Ultimately this UX methodology should be included in a larger UX strategy that’s accompanied with user research & usability testing.

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