Challenge
Signal faced a fundamental tension between security and ease of use. Users often struggled with onboarding, contact discovery, and understanding core privacy concepts.

Additionally, Signal lacked a username interaction model, making phone numbers the primary identifier—an approach limited adoption. However, introducing usernames posed its own set of challenges: How should they be verified? What visibility settings should exist? And how could Signal implement them without compromising security?

Solution
As a usability expert, I conducted in-depth research to bridge the gap between security and usability. My work included:

• Usability testing & user interviews. Understanding how users perceive privacy, security, and ease of access in communication apps.
• Competitive analysis. Examining how other platforms handled usernames, verification, and searchability.
• Human-centered design recommendations. Proposing a username system, suggestions to reduce friction in the onboarding process, and positioning recommendations.

My research highlighted that many users conflated security with privacy, failing to recognize distinctions in metadata handling, centralization, and trust models. This led to a broader strategy shift—moving beyond UI improvements to integrating educational elements that clarified Signal’s unique value.

Outcome
My research helped shape Signal’s approach to usability as they were transitioning from a small founder-led team to the Signal Foundation we know today.  By aligning usability with Signal’s core mission, this work contributed to making privacy-first communication more accessible and widely avaiable.