Article

Why GrowthBook + Feature Flags Are a Game-Changer for MVPs - with Flutter Examples

by Gary Worthington, More Than Monkeys

You’ve got a great idea, you’ve found a gap in the market. You’ve convinced some early users to give your app a try. So far, so good.

But building an MVP (Minimum Viable Product) isn’t just about shipping something quickly - it’s about shipping something adaptable. That’s where feature flags come in. And GrowthBook is one of the smartest ways to manage them.

This article explains:

  • What feature flags actually are (in plain English)
  • Why they’re critical for MVPs and early-stage apps
  • How GrowthBook makes this powerful and easy
  • How to implement this in a Flutter mobile app

What are feature flags?

A feature flag (also known as a feature switch or toggle) is a simple idea:

It lets you turn parts of your app on or off remotely without needing to publish a new version.

Think of it like a light switch. You’ve written the code for a new feature say, a “Nearby Deals” section in your app. Instead of showing it to everyone right away, you wrap it in a switch. That switch can be controlled from outside the app.

So:

  • You release your app with the feature hidden.
  • You turn it on for 5% of users to see what happens.
  • If something breaks, you turn it off instantly. No app update needed.

That’s the essence of feature flagging.

Why it’s perfect for MVPs

When you’re building an MVP, you’re not just writing code, you’re searching for the right thing to build. And that means you’ll want to:

  • Test new ideas quickly
  • Minimise risk when deploying changes
  • Experiment with UX and onboarding flows
  • Run A/B tests to guide decisions with real data

Feature flags let you do all of this without constant rebuilds, app store submissions, or risky big-bang launches.

Instead of wondering “Will this new idea break our app or confuse users?”, you just flip a flag. If it works, great, scale it up. If not, roll it back with a click.

Enter GrowthBook: feature flags + experimentation made easy

GrowthBook is a modern, open-source platform that makes feature flags and experimentation seamless. I am not being paid by Growthbook to write this post, I am just a fan. Other feature flagging platforms are available such as Launch Darkly, Optimizely etc.

Why GrowthBook?

  • ✅ Easy-to-use dashboard to manage your flags
  • ✅ Lightweight SDKs for mobile, web, backend
  • ✅ Built-in A/B testing so every flag can be an experiment
  • ✅ Privacy-first: use your own data warehouse
  • ✅ Works with Flutter, React, Django, and more

You get the control of a mature flagging platform with the speed of a startup-friendly tool, and no vendor lock-in.

📱 How this looks in a Flutter mobile app

Let’s say you’re building a travel app MVP, and you’ve got a new “Nearby Deals” carousel you want to test. Here’s how to manage this with GrowthBook and Flutter.

Step 1: Add the GrowthBook SDK

final growthbook = GrowthBook(
  clientKey: 'YOUR_CLIENT_KEY',
  attributes: { 'userId': currentUser.id },
);

This connects your app to the GrowthBook platform and allows it to fetch which features should be active for this user.

Step 2: Wrap your new feature in a flag

if (growthbook.isOn('showNearbyDeals')) {
  return DealsCarousel(deals: deals);
} else {
  return SizedBox.shrink();
}

The "showNearbyDeals" flag is now controlling whether users see the carousel.

Step 3: Control rollout via GrowthBook dashboard

In the GrowthBook UI, you create the flag showNearbyDeals, and set its behaviour:

  • Initially: OFF
  • Then: ON for 10% of users
  • Monitor results
  • Gradually increase to 50%, then 100% — or turn it off instantly if things go wrong

No app redeploy. No new build. No approvals needed.

Want to A/B test instead?

Let’s say you’re not sure whether to put the “Nearby Deals” carousel at the top of the screen or halfway down.

In GrowthBook, you can turn your flag into an experiment, assigning half your users to version A and half to version B. Then you track which version leads to more deals clicked, or longer session time.

Let real user behaviour guide your product, not guesses.

⚙️ Advanced: Dynamic UI via JSON config

You can go beyond just on/off flags. GrowthBook supports passing configuration to your app via JSON.

In your dashboard:

{
  "maxItems": 5,
  "animation": "fade"
}

In Flutter:

final config = growthbook.getFeatureValue('dealsCarouselConfig', defaultValue: {});
final maxItems = config['maxItems'] ?? 5;
final animation = config['animation'] ?? 'none';

return DealsCarousel(maxItems: maxItems, animation: animation);

Now you can control:

  • How many items to show
  • What animation style to use
  • Whether to show the component at all

all without updating your app.

What this unlocks for your MVP

Let’s summarise the benefits.

Feature flag benefitImpact on MVP devDecouple deploy & releaseShip fast, activate laterReduce risk of bugsRoll out gradually, roll back instantlyExperiment rapidlyLearn what users prefer, with dataRemote configChange behaviour without code changesFocus on outcomesAlign features to metrics from day one

If your MVP is mobile-first and you’re moving fast, feature flags with GrowthBook are your secret weapon. They let you move with confidence, learn quickly, and avoid the “Oh no, we need another build” panic.

Bonus: GrowthBook + AI-powered development

For teams using AI pair-programming tools (Cursor, VS Code extensions, etc), GrowthBook even supports an MCP Server that lets your editor create and manage feature flags via GPT-style prompts.

Just say “create a flag for new onboarding flow”, and it auto-inserts the SDK call, configures the flag, and sets it up in the dashboard.

No context-switching. Just faster dev cycles.

Final thoughts

MVPs live or die by how fast they learn. Feature flags let you learn without breaking things. GrowthBook gives you the tooling to do that responsibly.

If you’re building a Flutter app and want:

  • A better way to launch features
  • Real insights from real usage
  • Less stress at deploy time

then GrowthBook should be in your stack from day one.

Gary Worthington is a software engineer, delivery consultant, and agile coach who helps teams move fast, learn faster, and scale when it matters. He writes about modern engineering, product thinking, and helping teams ship things that matter.

Through his consultancy, More Than Monkeys, Gary helps startups and scaleups improve how they build software — from tech strategy and agile delivery to product validation and team development.

Visit morethanmonkeys.co.uk to learn how we can help you build better, faster.

Follow Gary on LinkedIn for practical insights into engineering leadership, agile delivery, and team performance