We Built 8 Apps in One Day Using Replit: Is It Actually Any Good?

TL;DR

During our AI Automation Hackathon, one thing became obvious very fast. Replit was the solution of choice that most of the Cubies opted for. Before we had fully committed to our coffees, half the room had already spun up a project, and by lunchtime, eight teams were building eight completely different applications. Some were dashboards. Some were assistants. One was a 3D experiment that now lives in the shared memory (and nightmares) of the entire agency.

So we asked the real question…

Is Replit actually good, or did it just match the slightly feral energy of hackathon day?

Here is what we found when everyone at Cube, from senior engineers to people who avoid code like the plague, put Replit through its paces.

We built eight working prototypes in one day.Replit was brilliant for speed and UI generation.It needed more help with logic, APIs and any task that required the patience of a saint.The big learning was simple. Build the logic first, then let Replit wrap a UI around it.

Why did we try it in the first place?

As an AI first agency, we are always looking for ways to turn ideas into something tangible with the help of our robot besties. Replit promises exactly that. It positions itself as a place where anyone can build real applications fast, even without years of engineering experience.

That made it perfect for a Cube-style test.Eight teams. Eight pain points. Eight hours. A mix of engineering, design, product, HR and marketing. No time for perfection. Plenty of time for vibe coding and surprises.

What did we ask replit to build?

Replit had to support a lineup of genuinely varied asks to solve Cube’s biggest pain points. Some of these would normally take weeks to meaningfully prototype.Replit got dropped into the deep end without warning:

• a PM meeting scheduler

• an HR policy chatbot

• a Figma to app comparison tool

• a podcast and webinar scheduling assistant

• a multi screen utilisation dashboard

• automated analytics event creation

• a 3D biomarker viewer

• a handful of experimental tools that made sense in the moment
  

What are Replit's Biggest Strengths?

Based on feedback from our cubies, Replit's three standout strengths were speed (generating working apps in minutes), ease of use (requiring minimal prompt detail), and automatic UI generation that looks professional without manual design work.

Speed 🕰

Replit creates functional prototypes in minutes. One Cubie summed it up perfectly.

"After an insanely quick start, my expectations became unreasonably high."

Sophie, COO, 3 Sided Cube

That set the tone for the day. Once people realised they could get something working before the kettle finished boiling, there was no stopping us!

UI quality 🪄

Multiple teams were surprised by how polished the UI outputs were. “Replit came up with great interface designs pretty quickly.”

Even rough logic looked respectable. This made demos far easier and meant beginners could build something that looked like a real product by the end of the day.

Built-in AI Features 🤖

Anything AI powered worked more smoothly than expected. Embeddings, chat behaviour and simple reasoning features were easy to set up. For teams who had previously fought with API wiring, this was a relief.

Simple prompts work best 🎯

Replit responded better to clarity than detail.A teammate put it simply: “Things worked quickly from fairly simple instructions.”

Exactly the kind of prompting vibe a hackathon needs.

What Are Replit's Main Limitations?

The biggest limitations we discovered were difficulty with complex logic, API integration challenges, a learning curve for complete beginners, cost constraints on the free tier, and limited debugging capability for specialised code.

Logic gets tricky📱

Replit is excellent at UI. It is less excellent at anything with multi step logic or branching conditions. One Cubie said it plainly. “Good at UI. Logic… much harder.”

We found the best structure was to build logic first and then let Replit generate the interface.

API Integration Struggles 🔄

Several teams ran into issues with third party APIs. Replit thrives when working in its own environment. It becomes more fragile when connecting to established systems.

Is Replit Good for Complete Beginners? 🤨

Replit has a learning curve for people with zero technical background. Without guidance, the platform can feel overwhelming despite marketing itself as accessible. Replit is more accurately described as "low-code" rather than "no-code." Some basic technical understanding or access to someone with coding knowledge significantly improves the experience.

One of our support team members' experience demonstrates this: "I tried to use Replit, found it incredibly confusing and overwhelming, and gave up."

Is Replit Free or Paid? 💸

Replit offers a free tier, but active development consumes the allowance quickly. One of our teams used up the free tier and "quite a chunk of the first month's allowance in one day."

For anything beyond light experimentation or learning, budget for Replit's paid tiers. The free version has usage limits that become constraints during intensive development sessions like our hackathons!

Can Replit Build Mobile Apps?

As of right now; not really. Replit currently only supports web applications and lacks the native components needed for proper iOS or Android development. You could technically use it to test user experience flows or prototype mobile concepts, but you'd have to bin all the code afterwards and rebuild from scratch. If you're planning a native mobile app, we would suggest saving yourself the hassle going down another avenue.

Security Concerns 🔐

Here's the bit that makes enterprise clients nervous: Replit owns the infrastructure your code lives on. If you're handling sensitive data or Personal Identifiable Information (PII), this is a problem. The platform's data protection guarantees aren't strong enough for GDPR-heavy projects or organisations with strict compliance requirements. Our advice? Keep Replit for internal tools and non-sensitive prototypes. For anything touching user data or requiring ISO standards, you need traditional development with proper security controls.

Debugging Specialised Code Is Difficult 🪰

Replit struggles to debug complex or specialised code, particularly with imported files. I was working with 3D files for example, and I found it really struggled to debug and iterate around this format.

When errors occur in more advanced implementations, Replit sometimes can't identify or fix the problem, requiring manual intervention or coding knowledge.

As you can see, even placing relatively simple hotspots around our (interesting) 3D model was a struggle...

5 things we would do differently next time?

• Build logic first, interface second

• Keep prompts clear and simple

• Pair beginners with someone technical

• Use Replit for early exploration, not production apps

• Assume you will need the paid tier

All easy adjustments that help teams get more out of the tool.

The million dollar question…should you use Replit?

If you want to build quickly and test ideas, absolutely! Replit is powerful for hack days, internal tooling, proof of concepts and early stage experimentation. It shortens the distance between idea and prototype in a way few tools can.

If you want to ship a production app, handle complex logic or integrate deeply with existing systems, it is not the right tool yet.

Final Thoughts

Replit did more than keep up with our hackathon. It helped unlock ideas faster, lowered the barrier for non-technical teammates and gave every team the confidence to experiment without getting stuck. The prototypes were better than expected and the learning curve was manageable once people p aired up.

Replit did its thing, but the real show was everything our teams created with it. Wanna know what those were? Find out here - the full hackathon write-up is waiting for you

WANT TO SEE HOW WE BUILD APPS THAT MAKE A REAL DIFFERENCE?

Take a look at our work

OR

Get in touch