# A website for your business > Custom website development with responsive design, e-commerce and SEO built in. Modern, high-performance websites from App369. Canonical: https://app369.com/service/web-apps/ From a few fast pages that bring in enquiries to a full web app with logins, payments and bookings. You get a written plan and a fixed price before work starts. **Under the hood:** Vue and Nuxt or React, in TypeScript, with Node.js and Firebase on Google Cloud when you need logins, payments or bookings. [**Get Started **→](https://app369.com/contact/) ## **Prefer a fixed price?** Fixed scope, fixed price, paid upfront. The work happens in writing; no call needed. - [**Web App MVP Sprint**from $6,000A scoped web app MVP in Vue/Nuxt or React, with a fixed quote after a $450 written scoping.](https://app369.com/fixed-price/web-app-mvp/) - [**AI-Built App Rescue**from $450A Lovable, Bolt or Cursor app checked end to end in 3 days, then its worst problems fixed at a fixed price.](https://app369.com/fixed-price/ai-app-rescue/) - [**MCP Connector for your SaaS**$2,500An MCP server over your existing REST API, so your product works inside Claude, and in ChatGPT with OAuth sign-in.](https://app369.com/fixed-price/mcp-server-for-saas/) What Simon builds ## **Web development services** 01 ### **Tailored Website Development** Built with Vue.js and Nuxt, App369's web applications are designed around your business needs, from brochure sites to feature-rich SaaS platforms. 02 ### **Responsive & Adaptive Design** Every website App369 builds is mobile-friendly and adapts automatically to different screen sizes, ensuring an excellent user experience across all devices. 03 ### **E-Commerce Development** App369 builds secure e-commerce platforms with integrated payment systems, inventory management, and smooth checkout processes. 04 ### **Search Engine Optimization** Simon optimizes your site for search engines to improve visibility, drive traffic, and increase engagement with your target audience. Error fixes ## Web app deploy and runtime errors Simon fixes Each page explains the error from the vendors’ own docs, with what to change next. - [Next.js Edge Runtime does not support Node.js module](https://app369.com/fix/nextjs-edge-runtime-node-module/) - [Vercel function exceeded 250 MB](https://app369.com/fix/vercel-function-250mb-limit/) - [Vercel npm run build exited with 1](https://app369.com/fix/vercel-npm-run-build-exited-with-1/) - [Next.js window is not defined](https://app369.com/fix/nextjs-window-is-not-defined/) - [Next.js Module not found: Can’t resolve fs](https://app369.com/fix/nextjs-cant-resolve-fs/) - [Vercel 404: NOT_FOUND](https://app369.com/fix/vercel-404-not-found-deployment-ready/) - [Next.js DynamicServerError](https://app369.com/fix/nextjs-dynamic-server-usage-error/) - [Vercel deployment blocked: commit author](https://app369.com/fix/vercel-deployment-blocked-commit-author/) - [Vercel ERR_TOO_MANY_REDIRECTS](https://app369.com/fix/vercel-err-too-many-redirects-cloudflare/) - [Next.js image host not configured](https://app369.com/fix/nextjs-image-unconfigured-host/) - [Next.js Server Action body limit](https://app369.com/fix/nextjs-server-action-body-size-limit/) - [Vercel preview asks to log in](https://app369.com/fix/vercel-preview-deployment-asks-to-log-in/) - [Netlify function timeout](https://app369.com/fix/netlify-function-timeout/) - [Vercel 413 payload too large](https://app369.com/fix/vercel-function-payload-too-large-413/) - [Vercel environment variables undefined](https://app369.com/fix/vercel-environment-variables-undefined/) - [Next.js hydration error](https://app369.com/fix/nextjs-hydration-error/) - [Vercel Module not found](https://app369.com/fix/vercel-module-not-found-cant-resolve/) - [Vercel FUNCTION_INVOCATION_FAILED](https://app369.com/fix/vercel-function-invocation-failed/) - [Next.js useSearchParams Suspense boundary](https://app369.com/fix/nextjs-usesearchparams-suspense-boundary/) - [Vercel function timeout 504](https://app369.com/fix/vercel-function-timeout-504/) - [Page not found on refresh](https://app369.com/fix/page-not-found-on-refresh-netlify-vercel/) - [Bolt or Lovable build fails on deploy](https://app369.com/fix/bolt-lovable-build-failed-netlify-vercel/) Questions ## **Frequently asked questions** ### **How much does web application development cost?** App369 uses Vue.js and Nuxt with SSR to maximize performance per dollar spent, reducing time-to-market by leveraging component-based architecture and automated deployment pipelines. ### **What web technologies does App369 use?** The stack includes TypeScript for type safety, TailwindCSS for utility-first styling, and server-side rendering (SSR) for optimal SEO performance. ### **How long does web app development take?** Simple marketing sites with CMS take 4-6 weeks, medium-complexity applications with user authentication and API integrations require 2-4 months, and enterprise SaaS platforms with real-time data, role-based access, and CI/CD deployment pipelines take 4-9 months. ### **Do you build progressive web apps (PWAs)?** Yes. App369 builds PWAs that work offline, load instantly, and can be installed on home screens without app store submission. These PWAs use service workers, the Web App Manifest, and Nuxt's built-in PWA module to deliver native-like experiences. ### **What is the difference between a website and a web application?** A website is primarily informational, displaying static or CMS-managed content to visitors. A web application is interactive software that runs in the browser, enabling users to create accounts, process transactions, manage data, and interact with APIs in real time. Examples include project management tools, CRM systems, and SaaS dashboards. App369 builds both, using Nuxt with SSR for content-heavy sites that need SEO visibility, and Vue.js SPAs with REST or GraphQL APIs for complex interactive applications. Fiverr reviews / 95 on app work ## **What buyers said about this kind of work** [**Read 126 of the 127 reviews **](https://app369.com/reviews/) - - - ### **Read the whole story** - [Sixteen five-star reviews from one buyer: mobile apps, app design and a Shopify store](https://app369.com/case-studies/fiverr/mobile-apps-and-a-shopify-store-for-one-buyer/) (Mark, United States) - [A large custom app build, delivered on the back end and the front end](https://app369.com/case-studies/fiverr/large-custom-app-build/) (A buyer in the United States) ## **Data and research** - [**Fixed-Price App Development Prices 2026**](https://app369.com/statistics/fixed-price-app-development-prices-2026/) What sellers publish for a bug fix, Stripe subscriptions, a rules audit, an AI-built app rescue and a web MVP. ![](https://app369.com/.netlify/images?w=44&h=44&url=%2Fimages%2Fszymon.jpg)****Simon Dziak****Founder and head developer ## **Get a personalized assessment by email** Submit your project details and Simon replies by email with a personalized assessment, usually within one business day. [**Get in touch **→](https://app369.com/contact/) [**Instant quote**](https://app369.com/instant-quote/) Prefer a call? [Consultations](https://app369.com/service/consultations/) are $100 per 15 minutes, paid upfront.