Yes, the 4G router service is definitely available and I suspect a growing number of people are opting for it as the cost of mobile data allowances seems to have dropped to very competitive levels with those of a landline. 4G is the way I'm looking to go but as Teflon said retaining our long-standing landline number without a landline is what I would like to do, but only for free or a one-off fee as per Google Voice. I suspect that a virtual landline might be the only way of doing it regardless of how it is advertised but I've not yet seen any free offers for that service and the only viable option for me would be Google Voice if it were available here in the UK. Google I think might offer a way of doing it in a roundabout way in the UK but not for a $20 one-off fee. From what I've read it is aimed at its business customers and requires a subscription to two of its services.
As I said earlier, Vodafone offers a service, it is called Vodafone Mobile Landline Service, but it is not free and is likely a virtual landline affair.
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