Features › Advanced Features

Web ↔ Mobile

Turn a deployed app into its other platform in one click — web → mobile or mobile → web — while keeping the same backend, database, and login.

What is this?

You built and deployed an app on one platform — say a web app — and now you want it on the other platform too. Emergent does that for you in one click.

Instead of re-prompting a brand-new project from scratch (and losing all your context), Emergent takes your existing app and rebuilds just the front-end for the new platform. Your backend, database, and login stay shared with the original app, so both versions read and write the same data.

Think of it like:

One product, two front doors — a web door and a mobile door into the same app
A copy of your app that already knows everything the original knows
The hard part (backend, data, auth) stays shared — only the screens get rebuilt

It works in both directions:

Web → Mobile — take your live web app and get a native iOS + Android app
Mobile → Web — take your mobile app and get a web app

Note

The two apps share one backend, one database, and one login system. A user who signs up on web is the same user on mobile, and their data shows up in both places automatically.

When should you use it?

Add a mobile app

You have a live web app and your users keep asking for an iOS / Android version. Convert it instead of rebuilding.

Add a web app

You started on mobile but need a web presence — a dashboard, a marketing site, or desktop access to the same data.

Reach users where they are

Some users want a browser, some want an app on their phone. Ship both from one project.

Keep data in one place

Web and mobile share the same accounts and the same data — not two separate, divergent backends.

How it works

Find the button

On any deployed app, open the preview / deployment panel and click "Create mobile version" (or "Create web version" if you're on a mobile app). The button only appears once your app is deployed, so deploy it first.

{/* 📷 Screenshot: preview panel showing the "Create [other-platform] version" button */}

Confirm the conversion

A confirmation modal explains what's about to happen — "We'll rebuild the front-end for [mobile / web]. Your backend, database, and login stay shared with this app. You can keep iterating on both apps independently afterward." Click Confirm to start.

{/* 📷 Screenshot: confirmation modal */}

Emergent builds your new app

Emergent creates a new, linked project and seeds the agent with your full source app — the front-end code, the backend, the live URL, your login setup, and your feature list. Because there's more to set up than a normal build, this takes a little longer — usually 3–5 minutes. Your original app keeps running, untouched, the whole time.

Answer a couple of quick questions

The agent asks a few clarifying questions to adapt your app to the new platform well (for example, how a particular screen should feel on a phone). Answer them, and it starts building — adapting layouts, navigation, and platform behavior for the target.

Deploy web, mobile, or both

When it's ready, you choose where it goes live — Web + Mobile, Only Web, or Only Mobile. Both apps share the same backend, so whatever you pick, the data stays in sync.

{/* 📷 Screenshot: "Choose platforms to deploy" (Web + Mobile / Only Web / Only Mobile) */}

Replace or deploy as new

By default, the new app is set up as a Replace Deployment — it takes over the live URL and experience of the original app. A confirmation modal makes this clear before anything changes, so you're never surprised. You can also deploy it as a separate app if you'd rather keep both live independently.

{/* 📷 Screenshot: "Confirm Replacement" modal (… goes live / … shuts down) */}

Keep building

From here, the new app behaves like any other Emergent project. You can prompt changes, iterate, fork it, and it consumes credits exactly like a normal build.

Note

Replace Deployment is the same mechanic used everywhere else on Emergent. If you're unsure what "replace" does to your data and URL, read Deployment Types first — especially the Replace Existing Deployment section.

What's shared vs. what's independent

This is the most important thing to understand about converting your app:

Layer	Web app	Mobile app
Backend code	Shared	Shared
Database & data	Shared	Shared
Login / accounts	Shared	Shared
Front-end code & screens	Independent	Independent
Deployment	Its own	Its own

Warning

Because the backend and database are shared, a change you make to the backend on one app affects both apps. The agent manages this for you, but keep it in mind: your two apps are two front-ends on one backend — not two fully separate products.

Your front-ends are independent, so visual and screen-level changes you make to the web app won't change the mobile app, and vice versa. The two designs are free to diverge.

Platform differences the agent handles

Some features exist on one platform but not the other. The agent adapts them automatically where it can, and tells you where it can't.

Web → Mobile

Browser-only features (like webcam access via the browser) are mapped to their native mobile equivalent where one exists.
If there's no clean equivalent, the agent skips it and explains the limitation instead of silently dropping it.
Login is adapted from web-style sessions (cookies) to mobile-style sessions (tokens) automatically.

Mobile → Web

Mobile-only features (push notifications, biometric login, deep links) fall back to a web-appropriate alternative, or are skipped with a note.

Tip

When the agent can't carry a feature across, it says so clearly — so you always know what made it to the new platform and what didn't.

Pricing

There's no separate fee and no Pro plan required. A conversion is just another build — it consumes credits like any other job. See Plans and Credits for details.

Best practices

Do this

Deploy your source app first — the button only appears on deployed apps.
Answer the agent's clarifying questions — a little detail up front gives you a much better result on the new platform.
Test the new app in Preview before you replace the live deployment.
Decide deliberately whether to replace the original deployment or deploy as a separate app.

Avoid this

Don't expect 1:1 feature parity — the agent does its best to adapt, but some platform-specific features change or drop. Read its notes.
Don't forget the backend is shared — a backend change is a change to both apps.
Don't replace your live deployment until you've checked the new app actually works.

Remember

✅ One click — web → mobile or mobile → web
✅ Backend, database, and login are shared — your data stays in one place
✅ Front-ends are independent — designs can diverge freely
✅ Takes ~3–5 minutes to build the new app
✅ Deploy web, mobile, or both
✅ Consumes credits like a normal build — no extra fee, no Pro gate
⚠️ Backend changes affect both apps — they share one backend by design

Common questions

Will my original app keep working?

Yes. Conversion creates a new, linked project and leaves your original app running untouched. You can keep using and forking the original at any time.

Do the two apps share the same users and data?

Yes. They share one backend, one database, and one login system. A user who signs up on web is the same user on mobile, and their data appears in both apps automatically.

Can I convert the same app more than once?

Yes. You can run multiple conversions from the same source app.

Can I convert an app I've already forked or iterated on a lot?

Yes. A long history of forks and changes is fine — conversion continues as a new project with its own deployment.

What if the build fails partway through?

You're left with a half-built linked project, but your original app is unaffected. Just go back to the original and start again (or fork from there).

What happens if I delete or unpublish the original app?

The new app keeps working as long as the shared backend is live. If you take the backend down on the original, the new app will stop working too — because they share it.

Can I split the backend apart later?

No. The shared backend is part of the design — the two apps are meant to stay connected. If you need a fully separate backend, build a separate project instead.

Can I make an admin / customer-facing variant instead of a different platform?

That's not the main purpose of this feature, but you can steer it when the agent asks its first questions — for example, asking for an admin-style web tool alongside your mobile app.

Need help?

If your conversion didn't go as expected:

Test in Preview before replacing your live deployment.
Go back to your original app — it's always safe and untouched; you can fork from there.

Still stuck? Reach out at support@emergent.sh.