I Built a 1M-View App on an Old Phone — Replit CEO Called It "Fantastic" & Gave Me Free Core

Hey everyone, I'm Lucas — just a web guy from Brazil 😄

A few weeks ago I launched MasterZap: a simple site that puts public leaked data from the Daniel Vorcaro / Banco Master case (stuff already out in G1, Folha, Metrópoles, etc.) into a WhatsApp-style chat viewer + graphs + AI summaries.

In one weekend: over 1 million views. All made on my Galaxy A11 phone using Replit's mobile app and Grok to help with code when I forgot React stuff after years away.

Then the free tier died under the load. I tweeted about it, open-sourced the repo, and emailed Amjad Masad (Replit CEO) directly.

He replied fast. Called the story "fantastic". Gave me Replit Core free for 3 months, featured in the community livestream, and invited me to their May hackathon in São Paulo (theme: corruption, elections, political education — fits perfect).

This is how it happened. No fancy setup, no team, just curiosity and persistence.

Why I Built It

When the leaks exploded, everything was scattered: screenshots, PDFs, news pieces. I thought: why not one place to read like real WhatsApp convos, search fast, see who connected to whom (graphs), and get quick AI resumes for the long boring parts?

Inspired by public archives like Epstein files, but 100% from open sources — media + official reports. Goal: make transparency easier for journalists, students, anyone curious. No drama, just facts.

The Stack (All on Phone!)

1. Frontend: React + Vite (Replit template)
2. Data: JSON parsed from public articles, vis.js or react-force-graph for connections
3. Search: fuse.js quick & dirty
4. AI: Grok (xAI) to fix my old React bugs, suggest components, even generate summaries
5. Deploy: Replit mobile — edit, console, preview right on 4G

Launch & The Viral Hit

Posted a short thread on X with a phone-recorded demo:
Link: https://master-zap--lucasmatheus20.replit.app/

Tagged some journalists

Day 1: hundreds. Then media mentioned it. Weekend: boom, 1M+ accesses. People said it felt like scrolling real chats but for public scandal data.
Until... success broke it. 502s everywhere. Free tier limits hit hard.
The Email to Amjad

I tweeted the crash, linked GitHub, and sent a direct email:
"Hey Amjad, built this on old Android + Replit mobile. Hit 1M views for transparency in Brazil, but free tier crashed. Any advice?"

Hours later: reply. He loved the underdog angle. "Fantastic!" Upgraded to Core (no more limits), promised livestream spot, hackathon invite.
Small email, huge doors. Sometimes asking directly changes everything.
What I Learned (Real Talk)

Phone + free tools + AI = enough today. No excuses if you want to build.
Launch ugly & iterate. Mine was rough (missing chats, basic mobile), but feedback came fast.

Be bold but grateful. Reaching CEOs works when you show real value + story.

Ethics matter. Only public data, sources linked, no sensationalism.
One person can move things. 1M views from a solo project on old hardware.

What's Next

MasterZap back stronger with Core (more messages, better graphs, AI upgrades)

Open-source forever

Hackathon in May — maybe build more public data tools
Keep inspiring: if I did this with Galaxy A11, imagine what you can do.

Thanks to @Replit and @amasad and Marcelo for believing in builders like me. And to Grok/xAI for the code help. ❤️

Check it out: https://master-zap--lucasmatheus20.replit.app/ (or fork the repo!)

If you're a dev with limited stuff: just start. Phone is enough now.