Global messaging app WhatsApp, which boasts over a billion users, was targeted by hackers last month in a breach that saw mobile devices attacked through the voice calling functionality of the app.

While WhatsApp hasn't specifically stated who or how many users were targeted, the platform urged users to update to the latest version of the app in order to protect their data and devices from hackers.

Unsure how to update your WhatsApp or how to check if you're already running the newest version? Here's everything you need to know:

If you're an iPhone user:

Open the App Store on your mobile device

Hit the tab 'updates' along the bottom right

If your WhatsApp has not been updated, a button will appear reading "update." Tap and allow your device to install the latest version

If your app has been updated, there will be no update button, just one that reads "open." No further action is required

If for any reason you have difficulty finding WhatsApp, search for it using the search tab on the bottom right

Ensure you are running the latest version: 2.19.51

If you're Team Android:

Open the Google Play Store on your mobile device

Tap the menu

Open the 'My Apps & Games' tab

If your WhatsApp requires an update, the tab will read "update." Tap and allow your device to install the latest version

If your app has been updated, there will be no update button, just one that reads "open." No further action is required

If for any reason you have difficulty finding WhatsApp, search for it in the Play Store

Ensure you are running the latest version: 2.19.134