Who is Mobile Simulator for?

Mobile Simulator is a consumer product built for frontend developers.

Is Mobile Simulator free?

Yes — Mobile Simulator is free to use.

What platforms does Mobile Simulator run on?

Mobile Simulator runs on the web and embeddable surfaces.

Is Mobile Simulator still maintained?

Unverified. Mobile Simulator has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.

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Mobile Simulator

msim.appDeveloper Tools

Mobile Simulator (MSIM) is a Chrome and Firefox browser extension that allows frontend developers to view and test real websites across multiple device sizes simultaneously. It provides side-by-side comparison, synchronized scrolling, device rotation, and realistic device frames directly within the browser. The tool helps catch mobile UI issues faster than traditional DevTools workflows and is used for development, QA, PR reviews, and client presentations.

FreeWebEmbeddable

Visit msim.app

Overview

5 features

In the Developer Tools space, Mobile Simulator takes a focused approach. It focuses on testing responsive website layouts across multiple device sizes and orientations without repeatedly switching Chrome DevTools. Mobile Simulator is a consumer product aimed at frontend developers. Mobile Simulator costs nothing to use. It ships for the web and embeddable surfaces.

Mobile Simulator first shipped in 2026. Among its 5 catalogued features are multi-device view, sync scrolling, and device rotation.

Multi-device view
Sync scrolling
Device rotation
Responsive testing
Device frames

Built with & integrations

Hosting

Google Cloud

Runs on

BrowserEmbeddable

Detected from

Google Cloud: x-cloud-trace-context header

Trust & compliance

Verified signals

HTTPSPrivacy PolicyFree tierStore-verified publisher

Legal

Indexing history

What PulseGate has recorded for this listing

Indexed21 Jul · 23:10 UTC
Mobile Simulator Extension MSIM: Responsive Viewer verified against its public source
Source: PulseGate · Open

Frequently asked questions about Mobile Simulator

What is Mobile Simulator?: Mobile Simulator focuses on testing responsive website layouts across multiple device sizes and orientations without repeatedly switching Chrome DevTools. It is catalogued under Developer Tools on PulseGate.
Who is Mobile Simulator for?: Mobile Simulator is a consumer product built for frontend developers.
Is Mobile Simulator free?: Yes — Mobile Simulator is free to use.
What platforms does Mobile Simulator run on?: Mobile Simulator runs on the web and embeddable surfaces.
Is Mobile Simulator still maintained?: Unverified. Mobile Simulator has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.
When did Mobile Simulator launch?: Mobile Simulator first shipped in 2026.

At a glance

Pricing: Free
Platforms: Web
Languages: English
First seen: 21 Jul 2026
Built for: frontend developers
Model: B2C
Solves: Testing responsive website layouts across multiple device sizes and orientations without repeatedly switching Chrome DevTools.

Registered as

Chrome Web Store: peipdddkaeomnfdenmkddkapeemjomnb
Firefox Add-ons: mobile-simulator-msim

Developer

Mobilesimulatormsim

Live coverage

Identity confidence: High · 90.4
Indexed: 21 Jul 2026
Lifecycle: Alive
First seen: Jul 2026
Last seen: 21 Jul 2026

Identity audit (13)

Slug: mobile-simulator-extension-msim-responsive-viewer-msim-app
Lifecycle state recorded: 21 Jul 2026
Verification state: Indexed for public listing
Listing state: Listed: yes
Index status: Included in index
Latest evidence snapshot: 21 Jul 2026
Timeline basis: Indexed-at chronology (no inferred launch/funding milestones).
Name from: Derived from the project's own page and URL.
Category from: Assigned by a language model.
Summary from: Taken from the project's own store listing.
Languages from: Detected by a language model, checked against the page's own declaration.
Last updated: 21 Jul 2026
Canonical URL: https://msim.app/

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