GenUI in Flutter: When AI Generates Interfaces, Not Just Text

A couple of weeks ago I attended Flutter Flight Plans, Google's event presenting a new generation of tools for AI-powered applications.
Among announcements about Firebase, Gemini optimizations, and Dart updates, one thing stood out above everything else: GenUI.

It's not another "generative AI" buzzword. It's a fundamental shift in how we think about chatbots, assistants, and any conversational interface.

The problem with traditional chatbots

You've spent years using AI-powered applications. You know exactly what happens:
User types something → LLM processes → App returns a paragraph of text.

And then, the user must:
✗ Read the entire paragraph
✗ Interpret what to do next
✗ Write again if the result wasn't what was expected
✗ Wait for another round of response

It's inefficient. It's frustrating. It's what large models were supposed to solve two years ago… and didn't.

"Instead of describing a list of flights in text, why not render an interactive carousel of cards? Instead of asking the user to write their preferences, why not generate sliders, date pickers, and checkboxes?"

What is GenUI really?

GenUI is an experimental Flutter SDK that allows AI models to dynamically generate visual interfaces, not just text.

The architecture is elegant and brutal in its simplicity:

Widget Catalog: you define what visual components the LLM can render (FlightCard, DatePicker, PriceSlider, etc.) with a JSON schema for each.
GenUiManager: coordinates the LLM, catalog, and UI. Converts widgets into "tools" that the model understands.
UiAgent: handles the bidirectional loop. User sends message → LLM interprets intent → generates JSON → UI is rendered → user interacts → feedback goes back to LLM.

The result: UI generated in real time, adapted to each user, without predefined static screens.

An example worth a thousand words

Imagine a flight booking app with GenUI.

User: "I need to travel from Madrid to Barcelona this week, max 150 euros, prefer afternoon"

Traditional flow: fill form → see table of results → manually filter → see details → more clicks → passenger form… 7+ screens, 15+ clicks.

GenUI flow: GenUI automatically generates:

Interactive calendar to adjust exactly which day (with integrated prices).
Time selector with visual animation.
Real-time price slider filter.
Carousel of dynamically rendered flights with booking buttons.
When the user taps a flight, GenUI generates a form exactly tailored to that flight and user.

No transitions, no screens, no "going back". A visual conversation.

 GenUI doesn't replace the LLM. It empowers it. The model is still the mind, but now it has visual "hands". 

Why now. Why Flutter.

Google didn't launch GenUI just to launch. There are technical and business reasons:

1. Chatbots don't sell anymore: every startup, every company has a chatbot. The market is saturated. Differentiation is now about experience. Living UI.

2. Firebase AI Logic needed a killer use case: Gemini API is available to everyone, but how do you monetize it? GenUI offers real use cases: booking, e-commerce, technical support.

3. Flutter is the ideal platform: single codebase for mobile, web, desktop. GenUI scales everywhere without fragmentation.

4. The timing is perfect: Dart 3.10 and Flutter 3.38 include AI Toolkit optimizations, Widget Previewer, and Genkit Integration. All pieces are in place.

What the community is saying

After Flight Plans, the r/FlutterDev subreddit exploded with curiosity. Indie devs are prototyping: educational assistants, e-commerce dashboards, personalized fitness apps.

The general sentiment: it's not hype without substance, it's genuinely revolutionary. But there's also realism: GenUI is experimental, the API will change, it requires thinking differently.

One developer wrote: "For the first time, the LLM isn't just a brain without a body. It has UI. It has agency. It can propose, not just respond."

Short-term opportunities (2025-2026)

🚀 Booking and travel startups

GenUI is made for travel: flight bookings, hotels, cars. The conversational + visual flow is the perfect match. Teams that master GenUI will be sought by founders.

🛍️ E-commerce and retail

Instead of infinite scroll, GenUI can generate personalized recommendations with dynamic UI. Product cards, interactive filters, carousels. All generated by the agent, not hardcoded.

🏥 Fintech and insurance

Complex forms becoming conversational experiences. Dynamic budgets, comparators, simulators. GenUI can generate the exact UI the user needs in that moment.

📚 Education and productivity

Personalized tutors, academic assistants. The tutor (LLM) generates the exact UI to teach: step by step, with interactive exercises, dynamically generated quizzes.

Real challenges

1. GenUI is experimental

It's marked as "Highly Experimental". The API changed dramatically during development, will keep changing. It's not production-ready for all cases yet.

2. Limited widget catalog

CoreCatalogItems offers basic components. Any real app needs to significantly extend the catalog with custom widgets. That's work, that's friction.

3. Privacy and data

The LLM needs context about what UI it can generate. How do you describe the catalog without sending sensitive information? How do you handle user data? Open questions.

4. Brand consistency vs. flexibility

If the LLM generates UI, how do you ensure it respects your branding, your design language, your color palette? Requires thoughtful architecture.

5. Cost

Each GenUI interaction potentially requires LLM calls. At scale, that becomes expensive. How do you cache? How do you optimize?

What's coming. The long-term vision.

Google has published a clear roadmap for GenUI:

Genkit Integration: official, not experimental. Genkit as backbone for agent orchestration.
UI Streaming: progressive rendering. Don't wait for the LLM to finish completely; show components as they're generated.
Full-screen composition: GenUI generating entire screens, not just surfaces. AI-driven navigation.
Dart Bytecode support: dynamic execution of generated logic. Maximum flexibility.
A2A (Agent-to-Agent): agents generating UI to communicate with other agents. Fully meta GenUI.

 In 2-3 years, GenUI could be as fundamental to Flutter as Widgets. No exaggeration. 

Why this matters for you as a developer

If you're senior in Flutter and looking to differentiate yourself, GenUI is the move.

Not because it's the "technology of the moment", but because it tackles a real pain: conversational applications that are still frustrating for users. GenUI makes them better. That's it.

Teams building GenUI experiences now will be the ones defining what conversational UX is in 2026-2027. CTOs will seek developers with that expertise. Startups will need it to compete.

And if you're a freelancer or contractor, clients in booking, travel, fintech will be specifically asking: "Can you do this with GenUI?"

Final reflection

I've spent years seeing AI promises that don't materialize, frameworks that disappear, buzzwords that die. GenUI feels different because it solves something concrete: conversational interfaces suck. It solves that.

It's not perfect, not for everything, requires thinking it through. But it's real.

If you already work with Flutter and Firebase, the overhead of experimenting with GenUI is minimal. If you want to get ahead of the curve, now is the time.

Already tried GenUI? Have a prototype? See limitations? Let's talk. The space is still small, there's much to explore and build.

Want to explore GenUI for your company or project?
I have experience with Firebase, Gemini, and agent architecture. I can help you understand if GenUI is the solution for your case.
Contact me here to discuss your idea or project.
Or if you prefer, discover my full portfolio here.