You can use an app called Ookla, which can be downloaded via the app store on your device or by going to their website. This can be impacted at slower connection speeds, so check your speed using a speed test app.
Wi-Fi requirements Your call quality will be at its best at 2Mb per second. If you move between Wi-Fi hotspots, this can sometimes cause disruption to your call. If your device shows that you’re connected to Wi-Fi, try restarting the router, as the issue may be with your Wi-Fi connection. If this doesn’t show, you’re not connected to Wi-Fi.
Unlike Skype or WhatsApp, Wi-Fi Calling lets you call all your contacts from your own number without conflicting with other apps. Find out more about the London Underground Wi-Fi. You'll need to register to access London Underground Wi-Fi and then you can use Wi-Fi Calling as normal. Wi-Fi Calling is a great way to stay in touch during your commute. If Wi-Fi Calling isn’t allowed on the hotspot network, the service won't work. If not, you'll get a message asking you to. You can use Wi-Fi Calling in public hotspots if the hotspot provider allows it. So your usage will come out of your monthly allowance or be charged at the same rate as you normally pay when using our network. You'll be charged in the same way as you normally would be when you make calls. But you can still use it to call international or premium rate numbers from the UK. Wi-Fi Calling doesn't work while you're abroad. You can find help setting up Wi-Fi Calling here. For iPhone, you’ll need to visit the settings menu to turn it on.
Android phones should have Wi-Fi Calling already set up. Make sure your phone’s software is up to date.
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