Responsive Checker - Mobile Simulator Pro · Last updated: July 20, 2026
Short version: This extension does not collect, store, transmit, sell, or share any personal data. Everything runs locally in your browser.
Responsive Checker - Mobile Simulator Pro does not collect any user data. Specifically, we do not collect:
The extension saves your preferences (selected devices, custom device sizes, zoom level, theme choice, and last tested URL) using Chrome's built-in chrome.storage API. This data stays on your device inside your browser profile, is never transmitted to any server, and is removed when you uninstall the extension.
| Permission | Why it's needed |
|---|---|
| activeTab / tabs | To read the URL of your current tab so the simulator can open it automatically, and to open the simulator page. |
| storage | To save your settings and custom devices locally on your device. |
| declarativeNetRequest | To adjust response headers so websites can be displayed inside the simulator's device frames. No request content is read or logged. |
| Host access (<all_urls>) | Required so you can preview any website you choose inside the device frames. The extension never reads, records, or transmits page content. |
We do not use third-party analytics, advertising networks, or external servers. The extension makes no network requests of its own — the only network traffic is your browser loading the website you chose to test, exactly as it would in a normal tab.
Screenshots you capture are generated locally and saved directly to your Downloads folder. They are never uploaded anywhere.
The extension does not knowingly collect any information from anyone, including children under 13, because it collects no information at all.