Common Issues
general
My App Works on My Computer but Not When I Share the Link
Everything looks perfect when you test your app on your own computer. But when you send the link to a friend, customer, or investor, they see errors, a blank page, or something completely broken. It's embarrassing and confusing.
This happens because your computer has a special setup that makes the app work — things like saved passwords, local files, or settings that only exist on your machine. When someone else opens the link, none of that is available, so the app falls apart.
It might also be that your app is still running only on your computer (localhost) and isn't actually published to the internet yet, even though you have a link that looks like it should work.
Error Messages You Might See
This site can't be reached
404 Not Found
Application error - check logs
Blank white page
Failed to load resource
Common Causes
- App isn't actually deployed — You're running it on your computer (localhost) and sharing a link that only works on your machine
- Missing environment variables — Secret keys and passwords are saved on your computer but weren't added to the hosting platform
- Database not connected in production — Your app talks to a local database on your computer, not one on the internet
- Mixed HTTP and HTTPS — Your live site uses HTTPS but some resources are loaded over HTTP, which browsers block
- Browser cache showing old version — You see the working version from your cache, but others get the broken deployed version
How to Fix It
- Test in a private/incognito window — Open your link in an incognito browser tab to see what others actually see
- Check your hosting platform — Make sure your app is actually deployed and the hosting shows it as "live" or "active"
- Add your secret keys to the hosting — Any passwords or API keys on your computer need to be added to your hosting platform's environment variables section
- Check the deployment logs — Look at your hosting platform for error messages during the build or deploy process
- Test on your phone — Open the link on your phone (not connected to your home WiFi) to confirm it works outside your network
Real developers can help you.
Pratik
SWE with 15+ years of experience building and maintaining web apps and extensive BE infrastructure
Mehdi Ben Haddou
- Founder of Chessigma (1M+ users) & many small projects
- ex Founding Engineer @Uplane (YC F25)
- ex Software Engineer @Amazon and @Booking.com
Anthony Akpan
Developer with 8 years of experience building softwares fro startups
Taufan
I’m a product-focused engineer and tech leader who builds scalable systems and turns ideas into production-ready platforms.
Over the past years, I’ve worked across startups and fast-moving teams, leading backend architecture, improving system reliability, and shipping products used by thousands of users. My strength is not just writing code — but connecting product vision, technical execution, and business impact.
Milan Surelia
Milan Surelia is a Mobile App Developer with 5+ years of experience crafting scalable, cross-platform apps at 7Span and Meticha. At 7Span, he engineers feature-rich Flutter apps with smooth performance and modern UI. As the Co-Founder of Meticha, he builds open-source tools and developer-focused products that solve real-world problems.
Expertise:
💡 Developing cross-platform apps using Flutter, Dart, and Jetpack Compose for Android, iOS, and Web.
🖋️ Sharing insights through technical writing, blogging, and open-source contributions.
🤝 Collaborating closely with designers, PMs, and developers to build seamless mobile experiences.
Notable Achievements:
🎯 Revamped the Vepaar app into Vepaar Store & CRM with a 2x performance boost and smoother UX.
🚀 Launched Compose101 — a Jetpack Compose starter kit to speed up Android development.
🌟 Open source contributions on Github & StackOverflow for Flutter & Dart
🎖️ Worked on improving app performance and user experience with smart solutions.
Milan is always happy to connect, work on new ideas, and explore the latest in technology.
Vlad Temian
15+ years shipping production infrastructure for startups. Former CTO at qed.builders (acquired by The Sandbox).
Cursor ambassador and agentic tooling builder.
I've scaled systems, automated deployments, and built observability tools for AI coding workflows. I specialize in taking vibe-coded apps from broken prototype to production-ready: fixing Supabase auth/RLS, Stripe integrations, deployment pipelines, and cleaning up AI-generated spaghetti.
I build tools in this space (agentprobe, claudebin, micode) and understand both sides: how AI generates code and why it breaks.
https://blog.vtemian.com/
MFox
Full-stack professional senior engineer (15+years). Extensive experience in software development, qa, and IP networking.
Krishna Sai Kuncha
Experienced Professional Full stack Developer with 8+ years of experience across react, python, js, ts, golang and react-native. Developed inhouse websearch tooling for AI before websearch was solved : )
PawelPloszaj
I'm fronted developer with 10+ years of experience with big projects. I have small backend background too
Tejas Chokhawala
Full-stack engineer with 5 years experience building production web apps using React, Next.js and TypeScript.
Focused on performance, clean architecture and shipping fast.
Experienced with Supabase/Postgres backends, Stripe billing, and building AI-assisted developer tools.
Describe what's wrong in plain English. No technical knowledge needed.
Get HelpFrequently Asked Questions
What does 'localhost' mean?
Localhost means the app is running only on your own computer. It's like a private preview. To let others see it, you need to deploy (publish) it to a hosting service like Vercel, Netlify, or Heroku.
Why does it work in my browser but not my friend's?
Your browser might be showing a cached (saved) version, or your computer has settings and passwords that the live version doesn't have. Always test in an incognito window to see the real version.