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Both will first be available in London, Leeds and Slough on certain devices initially
O2 has launched 4G and WiFi calling services today bringing it inline with operator rivals in the UK.
4G Calling will initially be available in London, Leeds and Slough with more cities rolling out in the coming months. WiFi calling is available nationwide.
O2 customers with the iPhone 7 or iPhone 7 Plus in those three regions will be able to utilise the features. More devices will be made compatible in future during O2’s gradual roll out.
Data is not consumed when making a call through either services, minutes will still be accounted for when making a traditional call. Calls seamlessly switch from WiFi to 4G and vice versa whilst the user is mobile.
Originally known as VoLTE, it runs on low frequency 800MHz spectrum making it more far reaching.
Joining the party
EE trialled WiFi calling and its VoLTE service – 4G Calling in 2014. Both became available nationwide in June last year.
Three was the first UK network to launch VoLTE technology in June 2015, dubbing it 4G Super-Voice. Vodafone launched a similar service in 2014 called HD Voice, which runs on its 3G network, but is not VoLTE.