View Localhost on Mobile: 5 Methods to Test Your Site on Phone (2026 Guide)

Your frontend looks perfect in Chrome DevTools responsive mode. Animations smooth, layout flawless, interactions responsive.

Then you open it on your actual phone and it's broken.

Button too small to tap. Janky scrolling. Slow load time. Input field disappears behind the keyboard. The browser toolbar covers your nav. All issues the desktop emulator never caught.

Here's what developers building with AI coding agents like Claude Code and Codex face: you ship features fast, but mobile testing is still manual. Your code runs on localhost, but your phone can't reach it. Most tutorials tell you to use ngrok without explaining when you actually need it.

In this guide, you'll learn 5 proven methods to view localhost on mobile devices, from the simplest same-network approach to secure tunneling solutions. Each method includes step-by-step setup, framework-specific examples for Vite, Next.js, and Remix, plus troubleshooting for common issues.

Whether you're testing a quick CSS change or demoing work-in-progress to your team, you'll know exactly which method fits your workflow.

Why Test Localhost on Real Mobile Devices?

Desktop browser emulators lie.

They simulate screen sizes and user agents, but they don't replicate actual device performance, touch interactions, or real network conditions. You can resize Chrome DevTools all day and still ship broken mobile experiences.

Touch interactions differ from mouse. A 44x44 pixel button feels spacious with a cursor. On a phone, your thumb covers it and the three buttons next to it. Hover states don't exist on touch devices. Swipe gestures behave differently than trackpad scrolling.

Actual device performance matters. Your M3 MacBook runs JavaScript instantly. A mid-range Android phone from 2022 stutters on the same bundle. Memory constraints are real. Battery drain from inefficient code only shows up on physical devices.

Browser-specific quirks are everywhere. Safari handles viewport units differently than Chrome. iOS Safari's bottom toolbar appears and disappears during scroll, breaking fixed positioning. Chrome on Android renders fonts with different anti-aliasing.

Real network conditions expose issues. Your local machine has zero latency to localhost. Mobile networks have 100-300ms latency, packet loss, and variable bandwidth. Images that load instantly on WiFi timeout on 4G.

When to test on mobile during your development flow:

• After implementing new UI components
• Before committing responsive CSS changes
• When debugging mobile-specific bugs
• During stakeholder demos
• Before production deployment
• After major feature implementation with Claude Code or other AI coding agents

Testing on real devices isn't optional, it's the only way to know what users actually experience.

Method 1: Same WiFi Network (Local IP Address)

Best for: Quick testing, no tool installation, trusted network environments

This is the fastest way to view localhost on mobile. If your computer and phone connect to the same WiFi network, your phone can access your computer's local IP address.

How It Works

Every device on your network gets a local IP address (like 192.168.1.5). When your dev server binds to 0.0.0.0 instead of 127.0.0.1, it accepts connections from any device on the network, not just your computer.

Step 1: Find Your Local IP Address

On Mac:

ifconfig | grep "inet " | grep -v 127.0.0.1

Or open System Settings → Network → WiFi → Details → TCP/IP → IPv4 Address

On Windows:

ipconfig

Look for "IPv4 Address" under your WiFi adapter (usually starts with 192.168 or 10.0)

On Linux:

ip addr show | grep "inet " | grep -v 127.0.0.1

You'll see something like 192.168.1.147, that's your local IP.

Step 2: Configure Your Dev Server

Most dev servers bind to localhost (127.0.0.1) by default, which only accepts connections from your computer. Change the host to 0.0.0.0 to accept connections from your network.

Vite:

// vite. config. js
export default {
 server: {
 host: '0.0.0.0',
 port: 3000
 }
}

Or use the CLI:

vite --host 0.0.0.0

Next.js:

next dev -H 0.0.0.0 -p 3000

Or in package. json:

{
 "scripts": {
 "dev": "next dev -H 0.0.0.0"
 }
}

webpack-dev-server:

// webpack. config. js
module. exports = {
 devServer: {
 host: '0.0.0.0',
 port: 8080
 }
}

Remix:

remix dev --host 0.0.0.0

Create React App:

HOST=0.0.0.0 PORT=3000 npm start

Or create a . env file:

HOST=0.0.0.0
PORT=3000

Step 3: Access From Mobile

Start your dev server. On your phone's browser, navigate to:

http://[YOUR-LOCAL-IP]:[PORT]

For example: http://192.168.1.147:3000

Your site loads just like on desktop, with live reload working through your dev server's Hot Module Replacement (HMR).

Troubleshooting Same-Network Method

Connection refused or timeout?

• Verify both devices use the same WiFi network (not guest network)
• Check firewall settings, allow incoming connections on your dev server port
• Confirm dev server runs on 0.0.0.0, not localhost
• Try disabling VPN temporarily if active

Site loads but HMR doesn't work?

• Some frameworks require additional WebSocket configuration for cross-device HMR
• Check your framework's docs for hmr. host or similar settings

Corporate network blocks connections?

• Use a personal hotspot from your phone instead
• Or use Method 2 (tunneling) to bypass network restrictions

Pros and Cons

Pros:

• Zero setup, no tools to install
• Fastest iteration (instant reload)
• Works offline (no internet required)
• Free

Cons:

• Both devices must be on same network
• Won't work on corporate networks with client isolation
• Can't share with remote teammates
• No HTTPS (matters for testing certain Web APIs)

Method 2: ngrok (Secure Public Tunnel)

Best for: Sharing with team, webhook testing, HTTPS requirement, demonstrating work-in-progress

ngrok creates a secure tunnel from a public URL to your localhost, giving your local dev server a temporary internet-accessible address with automatic HTTPS.

What Is ngrok?

ngrok is a tunneling service that exposes localhost to the internet through a public URL. When someone accesses the ngrok URL, traffic routes through ngrok's servers to your machine.

Installation

With npm:

npm install -g ngrok

Or download the binary: Visit ngrok.com/download and follow platform-specific instructions.

Sign up (optional but recommended): Free accounts get longer session times and custom subdomains.

ngrok config add-authtoken <YOUR_TOKEN>

Basic Usage

Start your dev server on any port (e. g., 3000):

npm run dev

In another terminal, start ngrok:

ngrok http 3000

You'll see output like:

Forwarding https://abc123.ngrok-free.app -> http://localhost:3000

Open https://abc123.ngrok-free.app on your phone. Your localhost is now accessible from anywhere with HTTPS included automatically.

Advanced Features

Custom subdomain (paid plans):

ngrok http 3000 --subdomain=myproject

Creates https://myproject.ngrok.app instead of random characters.

Password protection:

ngrok http 3000 --basic-auth "user:password"

Inspect traffic: Open http://127.0.0.1:4040 while ngrok runs to see all requests, responses, and replays, useful for debugging webhooks.

Free vs Paid Tiers

Free tier:

• Random URLs
• 40 connections/minute
• 1 simultaneous tunnel
• Session timeout after 2 hours

Paid tiers ($8-25/month):

• Custom subdomains
• Multiple tunnels
• No timeout
• IP whitelisting
• Custom domains

For mobile testing during development, free tier works fine.

Pros and Cons

Pros:

• Automatic HTTPS
• Share with anyone (send link to team)
• Works across any network
• Reliable service with good uptime
• Traffic inspection UI

Cons:

• Requires internet connection
• Free tier has session limits
• Random URLs on free tier (harder to remember)
• Slight latency from proxying
• Security risk if you expose sensitive data

Method 3: Tailscale Funnel (Private Network Tunnel)

Best for: Security-conscious teams, private network testing, team collaboration with controlled access

Tailscale Funnel lets you securely expose localhost through an encrypted private network without sending traffic through public proxy servers.

What Is Tailscale Funnel?

Tailscale creates a private mesh network (VPN) between your devices. Funnel extends this to allow public HTTPS access while keeping your IP address hidden and all traffic end-to-end encrypted.

Unlike ngrok, traffic doesn't decrypt at a relay server, it goes directly from the client to your machine through Tailscale's encrypted tunnel.

Setup Requirements

1. Install Tailscale on your development machine
2. Create a Tailscale account
3. Enable Funnel in your Tailscale admin console

Installation:

# Mac
brew install tailscale

# Linux
curl -fsSL https://tailscale. com/install. sh | sh

# Windows
# Download from tailscale. com

Using Tailscale Funnel

Start your dev server:

npm run dev

Enable Funnel for your port:

tailscale funnel 3000

Tailscale gives you a URL like:

https://your-machine-name. your-tailnet. ts. net

Access this URL from any device, mobile, tablet, remote teammate's laptop.

How It's Different From ngrok

Privacy: Your real IP stays hidden. ngrok URLs can expose origin server info.

Encryption: End-to-end encrypted. ngrok decrypts at relay servers.

Access control: Restrict by Tailscale identity. ngrok requires custom auth.

Persistence: URL stays consistent across sessions (based on machine name).

Pros and Cons

Pros:

• Enhanced security and privacy
• Consistent URLs (not random)
• Access control through Tailscale network
• No session timeouts
• End-to-end encryption

Cons:

• Requires Tailscale setup (more complex initial config)
• Both you and collaborators need Tailscale for full features
• Less known than ngrok (harder to find help)
• Newer tool (smaller community)

Method 4: GitHub Codespaces Port Forwarding

Best for: Cloud development environments, remote teams, GitHub-centric workflows

If you use GitHub Codespaces for development, you already have built-in localhost forwarding without installing tunneling tools.

How Codespaces Port Forwarding Works

When your dev server starts in a Codespace, GitHub automatically detects the port and creates a forwarding URL.

Setup

1. Open your project in a Codespace
2. Start your dev server (e. g., npm run dev)
3. Click the "Ports" tab in VS Code
4. Right-click the port → Change Port Visibility

Three sharing options:

• Private: Only you can access (default)
• Private to Organization: Team members with repo access
• Public: Anyone with the URL

The URL format:

https://CODESPACE-NAME-PORT.app.github.dev

Mobile Access

Copy the forwarded URL and open it on your phone. It works exactly like localhost with HTTPS included automatically.

Pros and Cons

Pros:

• Zero setup if already using Codespaces
• HTTPS by default
• Team sharing built-in
• No external tunneling service needed
• Consistent with GitHub workflow

Cons:

• Requires GitHub Codespaces subscription
• Slightly slower than local development
• Depends on internet connection
• Not true localhost (cloud environment)

Method 5: Deploy Preview Environments

Best for: QA testing, stakeholder demos, production-like testing

Services like Vercel, Netlify, and Render automatically create preview URLs for every branch or pull request.

How Preview Deployments Work

Push a branch → Platform detects changes → Deploys preview → Generates unique URL

This isn't technically localhost, but it's common for mobile testing workflows because previews deploy your actual built code in a production-like environment.

Vercel

Setup:

npm install -g vercel
vercel

Or connect your GitHub repo in the Vercel dashboard. Every git push triggers a preview deployment with a URL like:

https://your-project-git-branch-username.vercel.app

Netlify

Connect repo in Netlify dashboard. Each pull request gets:

https://deploy-preview-123--your-site.netlify.app

Netlify's mobile "drawer" overlay lets you test different screen sizes and provides sharing links.

When to Use Preview Deployments vs Localhost

Use preview deployments when:

• Testing production builds
• Sharing with non-technical stakeholders
• Running automated tests in CI/CD
• Verifying build-time errors

Use localhost methods when:

• Actively developing (faster iteration)
• Debugging with dev server hot reload
• Testing features not ready for commit
• Need instant feedback on changes

Pros and Cons

Pros:

• Production-like environment
• Shareable with anyone
• HTTPS included
• Git-integrated workflow
• Built-in collaboration features

Cons:

• Slower iteration (must commit + wait for build)
• Not true localhost (requires deployment)
• Uses build minutes (potential cost)
• Can't test uncommitted changes

Comparison Matrix: Which Method to Choose?

Decision framework:

Choose same-network method if:

• You need the fastest feedback loop
• Testing quick UI changes
• Both devices on same WiFi
• Don't need to share with others

Choose ngrok if:

• Need to share work with teammates
• Testing webhooks (Stripe, Twilio, etc.)
• Require HTTPS for Web APIs
• Want traffic inspection tools

Choose Tailscale Funnel if:

• Security and privacy are priorities
• Building for enterprise/sensitive data
• Want persistent URLs across sessions
• Team already uses Tailscale

Choose Codespaces forwarding if:

• Already developing in Codespaces
• Distributed remote team
• Want GitHub-integrated workflow

Choose deploy previews if:

• Need production-like testing
• Sharing with non-technical stakeholders
• Running automated tests
• Can wait for build time

Framework-Specific Configuration Examples

Vite (Recommended 2026 Standard)

// vite. config. js
import { defineConfig } from 'vite'

export default defineConfig({
 server: {
 host: '0.0.0.0',
 port: 3000,
 hmr: {
 // Uncomment if HMR doesn't work on mobile
 // host: 'YOUR-LOCAL-IP'
 }
 }
})

Start with: npm run dev (if using config) or vite --host 0.0.0.0

Next.js

Option 1 - CLI flag:

next dev -H 0.0.0.0 -p 3000

Option 2 - package. json script:

{
 "scripts": {
 "dev": "next dev -H 0.0.0.0"
 }
}

Remix

remix dev --host 0.0.0.0 --port 3000

Or in remix. config. js:

export default {
 devServerBroadcastDelay: 1000,
 devServerPort: 3000
}

Note: Remix 2. x uses remix-serve and respects HOST environment variable.

Astro

// astro. config. mjs
export default {
 server: {
 host: '0.0.0.0',
 port: 3000
 }
}

SvelteKit

// svelte. config. js
const config = {
 kit: {
 adapter: adapter()
 }
}

Then run with:

npm run dev -- --host 0.0.0.0

Vue CLI

// vue. config. js
module. exports = {
 devServer: {
 host: '0.0.0.0',
 port: 8080
 }
}

Angular

ng serve --host 0.0.0.0 --port 4200

Remote Debugging Tools

Viewing localhost on mobile is step one. Debugging what you see is step two.

Chrome DevTools (Android)

Requirements:

• Android device with USB debugging enabled
• Chrome on desktop
• USB cable

Setup:

1. Enable Developer Options on Android (Settings → About Phone → tap Build Number 7 times)
2. Enable USB Debugging (Settings → Developer Options → USB Debugging)
3. Connect phone to computer via USB
4. Open Chrome on desktop → chrome://inspect
5. Your phone appears under "Remote Target"
6. Click "Inspect" to open DevTools for mobile browser

Full desktop DevTools now control your mobile browser, inspect elements, view console logs, debug JavaScript, check network requests.

Safari Web Inspector (iOS)

Requirements:

• Mac computer (required)
• iPhone/iPad with Safari
• Lightning/USB-C cable

Setup:

1. iPhone: Settings → Safari → Advanced → Web Inspector (enable)
2. Mac: Safari → Settings → Advanced → Show Develop menu
3. Connect iPhone to Mac via cable
4. Open your localhost URL in mobile Safari
5. Mac Safari → Develop → [Your iPhone] → Select the page

Safari Web Inspector opens with full debugging capabilities.

Alternative for non-Mac users: Use ngrok + Chrome DevTools, or cloud-based testing services like BrowserStack (paid) for iOS debugging without a Mac.

Testing HTTPS Locally on Mobile

Modern Web APIs (geolocation, camera, microphone, clipboard) require HTTPS. Localhost works over HTTP on desktop, but mobile browsers enforce stricter security policies.

Why HTTPS Matters

Try accessing navigator.geolocation over HTTP on mobile, it fails. Same with Service Workers, Web Crypto API, Notifications, and many others. They require a secure context (HTTPS).

Solution 1: Use Tunneling Services (Automatic HTTPS)

ngrok, Tailscale Funnel, and Codespaces all provide HTTPS automatically. No configuration needed.

ngrok http 3000
# → https://abc123.ngrok-free.app (HTTPS enabled)

This is the easiest path if you're already using tunneling.

Solution 2: mkcert (Local HTTPS Certificates)

mkcert generates locally-trusted SSL certificates so your dev server runs over HTTPS.

Installation:

# Mac
brew install mkcert

# Windows (Chocolatey)
choco install mkcert

# Linux
# See: github. com/FiloSottile/mkcert

Generate certificates:

mkcert -install
mkcert localhost 192.168.1.147

This creates localhost+1.pem and localhost+1-key.pem.

Configure your dev server:

Vite:

import fs from 'fs'

export default {
 server: {
 https: {
 key: fs. readFileSync('./localhost+1-key.pem'),
 cert: fs. readFileSync('./localhost+1.pem')
 },
 host: '0.0.0.0'
 }
}

Next. js: Next. js doesn't support HTTPS in dev mode by default. Use a reverse proxy like local-ssl-proxy:

npm install -g local-ssl-proxy
next dev
local-ssl-proxy --source 3001 --target 3000 --cert localhost+1.pem --key localhost+1-key.pem

Access via https://localhost:3001 or https://192.168.1.147:3001.

Install certificate on mobile:

For iOS: AirDrop the .pem file → Install profile → Settings → General → About → Certificate Trust Settings → Enable

For Android: Settings → Security → Install from storage → Select certificate file

Now your mobile device trusts your local HTTPS certificates.

Troubleshooting Common Issues

ERR_CONNECTION_REFUSED or Timeout

Cause: Phone can't reach your computer.

Fixes:

• Verify both devices use the same WiFi network
• Check your computer's firewall, allow incoming on dev server port
• Confirm dev server binds to 0.0.0.0, not 127.0.0.1
• Disable VPN temporarily if active
• Try pinging your computer's IP from your phone (use network utility app)

Site Loads But Changes Don't Update

Cause: Hot Module Replacement (HMR) WebSocket doesn't work cross-device.

Fixes:

• Configure HMR host in your dev server config:

// vite. config. js
server: {
 hmr: {
 host: '192.168.1.147' // Your actual IP
 }
}

• Use browser hard refresh (clear cache) manually
• Check firewall allows WebSocket connections on your port

SSL Certificate Errors with HTTPS

Cause: Mobile device doesn't trust your local certificate.

Fixes:

• Use tunneling service (ngrok auto-provides trusted certs)
• Install mkcert root certificate on mobile device
• Add security exception in mobile browser (not recommended for production testing)

ngrok Session Expired

Cause: Free tier has 2-hour session limits.

Fixes:

• Restart ngrok (ngrok http 3000 again)
• Sign up for ngrok account (extends session time)
• Use Tailscale Funnel (no timeouts)
• Use same-network method (no session limits)

VPN Blocks Local Network Access

Cause: Corporate VPN routes all traffic through VPN server, blocking local network.

Fixes:

• Disconnect VPN temporarily while testing
• Use tunneling service (bypasses local network)
• Use split-tunnel VPN config (if your company allows)
• Create personal hotspot from phone and connect laptop to it

Using AI Coding Agents for Mobile Testing Setup

Claude Code, Cursor, and other AI coding assistants can automate mobile testing setup.

Claude Code Commands

If you use Claude Code, ask it to configure mobile testing:

Set up my Vite dev server to be accessible from mobile devices on my network. Include the IP address lookup command and vite. config. js updates.

Claude Code will:

1. Find your local IP address
2. Update vite. config. js with host: '0.0.0.0'
3. Provide instructions for accessing from mobile
4. Set up HMR configuration if needed

Or ask it to install ngrok:

Install ngrok and set up a tunnel for my dev server running on port 3000.

Claude Code handles installation, authtoken setup, and starting the tunnel.

GitHub Copilot Prompts

In your config file, write a comment:

// Configure dev server for mobile testing with host 0.0.0.0 and HMR

Copilot suggests:

export default {
 server: {
 host: '0.0.0.0',
 port: 3000,
 hmr: {
 protocol: 'ws',
 host: 'localhost'
 }
 }
}

Automation Scripts AI Can Generate

Ask your AI assistant to create a script that:

1. Detects your local IP
2. Updates your config file
3. Starts your dev server
4. Prints the mobile-accessible URL
5. Optionally starts ngrok

Example prompt:

Create a bash script that finds my local IP address, starts my Vite dev server on 0.0.0.0, and prints the URL I should use on my mobile device.

AI coding agents speed up repetitive setup tasks, letting you focus on building features and testing on mobile devices faster.

Best Practices for Mobile Testing

Test early and often. Don't wait until right before deployment to check mobile. Test major features on actual devices during development.

Keep devices charged and ready. Have your test devices within reach while coding. The easier they are to grab, the more you'll test.

Test on multiple devices if possible. iPhone and Android render differently. Low-end devices expose performance issues high-end devices hide.

Use same-network method for active development. It's fastest for rapid iteration. Switch to tunneling when you need to share or need HTTPS.

Document your team's testing workflow. Write down which method your team uses, how to set it up, and where to find credentials. New developers shouldn't spend an hour figuring out how to test on mobile.

Set up security rules if using tunneling services. Add authentication, restrict IPs, or use Tailscale's access controls if exposing internal work.

Clear mobile browser cache regularly. Service Workers and aggressive caching can make your phone show old versions of the site even after you update code.

Integrate Mobile Testing Into Your Workflow

If you use Vicoa to manage AI coding sessions with Claude Code or Codex, mobile testing fits naturally into your workflow.

Start a coding session on your laptop. Claude Code builds the feature. You get a notification on your phone when it needs approval. Review the code on mobile, test the changes on your device using one of these methods, approve from anywhere.

Vicoa mobile app lets you manage coding agents from any device. When you're testing frontend changes on your phone, you can simultaneously review diffs, approve changes, and continue development, all from the same device you're testing on.

Start a remote session and code from anywhere while testing on the go.

Frequently Asked Questions

Can I test localhost on iPhone without a Mac?

Yes. Use ngrok, Tailscale Funnel, or Codespaces forwarding, all work on iPhone without needing a Mac. The Mac requirement only applies to Safari Web Inspector (remote debugging).

Do I need to be on the same WiFi network?

Only for the same-network method (Method 1). Tunneling services (ngrok, Tailscale) work across different networks. You can test on your phone using mobile data while your laptop is on WiFi.

Is ngrok safe to use?

Yes for development. Don't expose production systems or sensitive data. Use authentication (--basic-auth) if sharing URLs with untrusted parties. Traffic passes through ngrok's servers, so they can theoretically inspect it (though they state they don't).

What if my company blocks tunneling services?

Use same-network method with a personal hotspot. Turn on your phone's hotspot, connect your laptop to it, then access your local IP from the phone. This bypasses corporate network restrictions.

How do I test on multiple devices simultaneously?

Same-network method or tunneling services both support multiple devices. One dev server can serve requests to multiple phones and tablets at once. Each device accesses the same URL.

Can I use mobile data instead of WiFi?

Yes with tunneling services (ngrok, Tailscale, Codespaces). The same-network method requires both devices on the same WiFi network, so it won't work with mobile data.

Start Testing Your Localhost on Mobile Now

You have 5 proven methods to view localhost on mobile devices:

Method 1: Same WiFi Network for quick personal testing with zero setup.

Method 2: ngrok when you need HTTPS, team sharing, or webhook testing.

Method 3: Tailscale Funnel if security and privacy matter most.

Method 4: GitHub Codespaces if you're already in a cloud dev environment.

Method 5: Deploy Previews for production-like testing with stakeholders.

Start with Method 1 (same network), it takes 30 seconds. Find your local IP, add host: '0.0.0.0' to your dev server config, and open the URL on your phone.

Then explore tunneling services when you need to share work or test HTTPS-required features.

Your desktop browser's responsive mode is useful for ballpark checks. Real devices are where you catch what actually breaks.

Test on your phone as you build. Ship features that work everywhere, not just on your laptop.