After what seems like an age of promising, Three has finally enabled baked-in Wi-Fi calling in to the iPhone. If you have an Apple iPhone and are on the Three network, you'll be able to make and receive calls and texts from anywhere you have a Wi-Fi connection, without the need for the company's separate InTouch app. 

The service is compatible with any iPhone launched since 2014, so that means the iPhone 5c, iPhone 5s, iPhone 6, iPhone 6s, iPhone SE and iPhone 7, that obviously includes any "Plus" models of those listed devices. 

Before switching on you need to ensure you have the latest software. That means making sure you're running iOS 10.2. To do that follow the following instructions: 

  1. Go to Settings > General > Software Update
  2. Download and install any software update that shows up, if none, proceed to the next step.

If you've downloaded the latest software, you should also make sure you have the latest carrier software package installed. This isn't always included in the software update by default, so you'll need to go through the following steps: 

  1. Head to Settings > General > About
  2. Wait a few seconds and you should see a "Carrier update available" message pop up

Once you have the latest software and carrier updates, follow the simple steps below: 

  1. Go to Settings > Phone
  2. Select "Wi-Fi Calling" 
  3. Toggle the "Wi-Fi Calling on This iPhone" switch to the on position
  4. Confirm that you want to activate the feature

As soon as it's been activated, if you're connected to a Wi-Fi network your "Three UK" network name in the status bar should now say "Three WiFi Call". 

Any time you see that message in your status bar, your calls and text messages will be made over Wi-Fi, which usually means you'll get better call quality.