ACS UI Library

Organization: Microsoft
Azure Communication Services
Role: Product lead and designer
Web, iOS, Android
Collaborators: Alex Pereira
Jessica Downey
Danielle Hibbs
20+ engineers
Duration: 2022 – Present

The ACS UI Library is the interface layer for Azure Communication Services — production-ready components for calling, chat, and real-time collaboration on web, iOS, and Android. It carries 11.1M+ monthly minutes and ships inside 200+ businesses.

I'm the product lead and the designer. I set the interaction model, made the visual calls, and wrote the specs, while owning the roadmap and customer work for the same features — 40+ shipped end to end with a team of 20+ engineers.

Everything here is designed through defaults. Developers adopt the library; their patients, customers, and agents just get whatever we shipped, without ever choosing it. So one control bar has to work in a telehealth appointment, a regulated financial call, and a contact center, and still be customizable enough that teams can make it theirs.

What I did

Interaction design: Set the models end to end — RTT panel behavior, call summary hierarchy, control bar overflow, pre-call device setup.
Visual design direction: Set the visual direction on every feature, down to the opacity model for RTT text states and component density on each platform.
Design strategy and roadmap: Decided what got designed and when, against accessibility deadlines, adoption gaps, and the platform's move toward AI.
Customer research: Interviewed Teladoc, CVS, OP Bank and others to find what was blocking adoption, then turned that into design priorities.
Cross-platform leadership: Led design across web, iOS, and Android at once, holding one interaction model steady across three engineering teams.
Accessibility: Drove the first Real-Time Text implementation at Microsoft, scoped for the European Accessibility Act deadline.

Selected work

Video gallery with participant tiles and the call control bar — Video gallery and call controlsThe default calling surface. Layout, speaker states, and control bar hierarchy that survive going from a two-person call to a full room.

Device setup before joining a call — Pre-call device setupCamera and microphone confirmed before joining. Get this wrong and people spend the first two minutes of a call troubleshooting.

The Real-Time Text panel during a call — Real-Time TextCharacter-by-character text for callers who can't use voice, kept at the same persistence as captions. The first RTT implementation at Microsoft.

The calling experience on a tablet in landscape — Mobile and tabletThe same interaction model across web, iOS, and Android, worked out again for one-handed use and smaller viewports.

Sample Builder configuration flow — Sample BuilderConfigure a scenario, theme it, deploy it. A team can find out whether the library fits before spending engineering time on it.

Diagram of the library's components layered on Fluent UI — Built on FluentCommunication components built on Microsoft's design system, so the library gets Fluent's accessibility and theming for free.

Outcome

One of ACS's most-used surfaces, shipping in healthcare, finance, automotive, retail, and enterprise products. Every composite meets WCAG 2.1 AA out of the box.

The full case study covers the decisions behind it: why in-progress text is dimmed instead of coloured, and why enabling RTT asks for consent.

11.1M+

Monthly minutes by the end of 2025, up from roughly 2M at the start of the year

200+

Businesses onboarded across healthcare, finance, automotive, and retail

40+

Features owned end to end, from first Figma frame to public release