WhatsApp has finally arrived on the web, but unfortunately not everyone will be able to use the service.

WhatsApp Web, which promises to "mirror conversations and message from your mobile device," is available for Android, BlackBerry, and Windows Phone, but iPhone users are out of luck.

Citing "Apple platform limitations," WhatsApp said that WhatsApp Web is unavailable on iPhones "for now," so the service could arrive on iOS devices in the future.

So how do you use WhatsApp Web?

WhatsApp Web offers the same messaging experience you're used to on your smartphone. Now it's just accessible from your web browser too.

To access WhatsApp Web, first make sure you have the latest version of WhatsApp downloaded on your smartphone. If you don't have WhatsApp, you can download it here.

Next, you'll need to install the Google Chrome web browser on your computer. If you don't have Chrome, you can download it here.

From within your Chrome web browser, head on over to https://web.whatsapp.com, where you'll be met with a QR code like the one below.

The last step is to open up WhatsApp on your smartphone and use it to scan the QR code. This pairs your web browser to your phone, and will enable you to see a mirror of all your conversations and messages.

It's important to note that WhatsApp Web only works if your phone is turned on and connected to the internet, so avoid turning it off or switching to airplane mode if you want the web client to work.