Almost eight months after WhatsApp Web debuted on Chrome and Android, the desktop web app for the messaging service now finally supports iOS. This means Apple users can keep their accounts and messages in sync between the web app and their iPhones.

WhatsApp Web was launched in January and supported Android, Windows Phone and Blackberry. The service never appeared on the iOS operating system due to "Apple platform limitations," but iPhone support is now finally rolling out in the latest update.

Any iPhone users wanting to try out WhatsApp Web need to first open WhatsApp on their phone, choose settings, and then select the WhatsApp Web menu (assuming it's appeared on the app). Users then need to go to WhatsApp's website, scan the QR code on the screen and the iPhone will begin pairing.

Once connected to the web app, conversations are mirrored; any action you take on the phone will apply to WhatsApp Web and vice versa. This offers the versatility of being able to start writing a message on a phone and finishing it on a desktop.

Although WhatsApp's 800 million users puts it ahead of competitors like Facebook messenger, Viber and Kik, it is yet to make headway into Asia, where services such as WeChat and Line dominate.

WhatsApp can boast almost four times as many monthly users as instant messenger rivals Kik, but the Canadian firm's recent $50 million investment from WeChat parent company Tencent may give it the financial muscle and resources to start mounting a serious challenge in the instant messenger market.