Sometimes a report is not enough. You want to open the menu, fill in the contact form, scroll through the product gallery and see how it actually feels on a phone. The MobileCheck phone window gives you that: your page in a window shaped exactly like the iPhone you pick, in your own browser, for as long as you need.
What the phone window is
The free MobileCheck extension opens your page in a separate window and sets it up like the device: the iPhone's CSS viewport and pixel ratio, touch input instead of a mouse, the iPhone's user agent, and dark mode if you switch it on. The page can't tell it apart from a phone, so it serves its mobile version — menus, sticky bars and all. Then you use it by hand:
- Tap and click links, buttons and menus, as touch input.
- Scroll and swipe through long pages, carousels and galleries.
- Type into search boxes and forms to see how inputs and validation behave.
- Switch devices to jump from a small iPhone SE to a Pro Max, an Android phone or an iPad, without losing your place.
- Rotate to landscape, turn on dark mode or large text, and take screenshots at the device's real resolution.
No Mac or Xcode needed, no account and no time limit. Because it runs in your browser, it also opens localhost, staging servers and pages you are signed in to.
One honest caveat: in the phone window the page is drawn by Chrome's engine, not by Safari's. Screen size, touch, user agent and layout breakpoints match the iPhone exactly, but Safari-specific rendering can differ. For that, run the check on this website, which renders iPhones with WebKit, the engine behind Safari. Things that come from iOS itself, such as native date pickers and the on-screen keyboard, need a real iPhone either way.
When the phone window is the right tool
It shines when a problem depends on interaction:
- A hamburger menu that opens but cannot be closed, or scrolls the page behind it.
- A form where the keyboard-friendly input types, labels or error messages need checking.
- Sticky headers, chat widgets and cookie banners that cover content as you scroll. See sticky headers and popups.
- Carousels, accordions and tabs that need swiping or tapping to reveal content.
- Hover menus: on a touch device there is no hover, so a menu that only opens on mouse-over won't open here either, exactly as on a real phone.
- Showing a client how their site behaves on an iPhone, during a call.
It is also a quick way to double-check a fix: if the report flagged a button as too small or a banner as covering the screen, open the same device after deploying the change and confirm it with your own eyes.
Phone window or the automated check?
The two tools answer different questions.
| Automated check (this website) | Phone window (extension) | |
|---|---|---|
| Best for | Finding problems you did not know about | Trying something specific by hand |
| Devices | Any or all 51 at once | One at a time, switch any time |
| iPhone engine | WebKit, Safari's engine | Chrome's engine, iPhone screen and user agent |
| Output | Screenshots, score, every issue explained | What you see, plus screenshots |
| Scenarios | Normal, dark mode, large text, menu opened | Whatever you do |
| Install | Nothing | Free Chrome extension |
A good routine: run the free check first to get the list of problems on several devices, fix them, then use the phone window to click through the parts that need a human, like the menu and forms.
Frequently asked questions
Is this a real iPhone?
No. It is your own Chrome set up exactly like the iPhone: the same screen size, pixel ratio, touch input and user agent, so websites show their iPhone version. The page is drawn by Chrome's engine, so for Safari-specific rendering use the check on this website, which runs WebKit.
Is the iPhone simulator free?
Yes. The MobileCheck extension is free, has no time limit and needs no account.
Does it work without installing anything?
The interactive phone window needs the free extension for Chrome, Edge or another Chromium browser on a computer. The automated mobile-friendly check on this website needs nothing installed.
Can I test an iOS app with it?
No. It is for testing websites. There is no App Store and it cannot install or run apps; for native apps you need Apple's Xcode Simulator or a real device.