Slack

This heuristic evaluates usability issues regarding Slack’s desktop application.

RoleHeuristic Evaluation
UX/UI Design

TeamArzu Oran
Teng Lin Shih
Idil Agcagul

How might we improve the usability of Slack’s desktop app?

PROBLEM

Heuristic evaluators have generally found Slack’s interface user-friendly, with smooth processes for creating workspaces, sharing, and adding channels. Yet, issues with the message pinning function and notification settings highlight the need for enhancements.

RECOMMENDATIONS

This heuristic evaluation has resulted in two practical recommendations to enhance the user experience of Slack:

Enhance the message pinning function for improved visibility and organization
Clarification on the naming of different notification settings

INTRODUCTION

Slack, launched in 2013, is a cloud-based collaboration tool with 32.3 million daily active users, designed to enhance productivity and communication within teams and organizations. It provides a centralized platform for real-time messaging, file sharing, and project collaboration through features like channels, direct messaging, and integrations with other productivity tools, enabling seamless teamwork regardless of location.

GOALS & MOTIVATIONS

This heuristic evaluation report on Slack aims to highlight underlying usability issues through assessments from usability experts on how well Slack works, alongside providing suggestions for improvement.

USERS & TASKS

Three usability experts evaluated 9 tasks for heuristic violations, ranked on a severity scale of 1 (Minor) to 4 (Critical)

Focus areas included:

Workspace and channel setup and sharing
Message sending, reactions, and pinning
Notification preferences and availability status
Third-party configurations

Key Findings

01

Pinned Messages are Easily Overlooked
Users expect a clearer visual indication when pinning a message, but there only seems to be a subtle change in color

Heuristics violated: Visibility of System Status & Recognition Rather than Recall

02

Notifications settings are Unclear
Slack’s custom notifications allow pausing alerts until a set time, but a separate notification schedule setting below serves a different purpose, despite similar wording.

Heuristics violated: Consistency and Standards & Recognition Rather than Recall

Recommendations

Recommendation #1

ISSUE

Pinned Messages Get Buried Under Multiple Messages

Pinned messages in Slack can become buried under new messages, reducing their visibility and effectiveness in prioritizing important information.

Pinning Feature Lacks Visibility

The pinning feature is only accessible through the ‘More actions’ tab when hovering over a message, and evaluators noted the need for clearer visual feedback, as the current subtle color change is insufficient.

RECOMMENDATION

Enhance the message pinning function for improved visibility and organization

Introducing a pin icon on hover would give users a quick and intuitive way to pin important messages. This streamlined process would make pinning more accessible and encourage more frequent use of the feature.

Secondly, keeping pinned messages visible at the top of the conversation thread would enhance their prominence, making it easier for users to reference important information without scrolling through the chat history.

Recommendation #2

ISSUE

Unclear Notification Settings

Slack’s ‘Pause Notifications’ tab includes two settings: ‘Custom...’ for pausing notifications until a set time, and ‘Set a notification schedule’ for managing notifications based on a schedule. However, unclear wording makes these settings seem similar.

‘Custom...’ window under pause notifications menu

‘Set a notification schedule’ page under pause notifications

RECOMMENDATION

Clarification on the naming of different notification settings

This adjustment clarifies that ‘Custom...’ pauses notifications until a set time, helping users differentiate it from ‘Set a notification schedule.’ Clearer wording reduces confusion and ensures users can easily choose their preferred settings.

CONCLUSION

Slack’s interface is generally user-friendly, but issues with message pinning and notification settings were identified. To improve usability, we recommend enhancing message pinning for better organization and clarifying the naming of notification settings.

NEXT STEPS

Implement recommended solutions to streamline Slack’s user interface
Provide users with clearer and more intuitive communication and collaboration tools
Enable users to easily access important messages

LEARNINGS

In this project, I learned how to conduct usability research using heuristic evaluation and how to write clear, multi-step tasks for the evaluators. This experience improved my ability to evaluate design systematically and showed me the value of detailed task breakdowns.

Read the detailed report here