With LTE connectivity now a standard feature on almost every middling smartphone, it might come as a surprise that the vast majority of Brits haven't had access to a next-generation network. A little under a year ago, EE turned on the first LTE network in the country, and thanks to a complex spectrum auction peppered with in-fighting and controversy, it's taken EE's main competitors 10 months to catch up. From this morning, customers of O2 and Vodafone in select cities will finally have access to LTE, with the fourth-largest carrier, Three, remaining the only one without some sort of 4G support. So which carrier should the discerning smartphone lover opt for?

Coverage

Mainstream carriers in the UK will offer LTE over just three frequencies. More specifically, there's LTE at 800MHz, which offers the best coverage when indoors, 2600MHz, which doesn't travel far and has poor penetration of buildings, and 1800MHz, which, as you may have guessed, is a compromise between the other two. As all carriers are using the same bands, users shouldn't have much trouble putting their LTE-ready SIM into an unlocked phone designed for use in Europe. It's a very different situation to the US, where the four national carriers run LTE service on a variety of disjointed bands.

EE, which offered the only LTE network in the UK for a long time, has coverage in the majority of big cities, including London, Manchester, Birmingham, Leeds, and Liverpool in England, Glasgow and Edinburgh in Scotland, and Cardiff in Wales. At the moment, its network runs at 1800MHz, but it also owns unused spectrum at 800MHz and 2600MHz, putting it in good stead for further expansion. EE says it plans to cover 98 percent of the UK with LTE by the end of next year.

O2 will offer coverage across 13 of the UK's largest cities by the end of year, and, as part of the deal for its spectrum, has committed to provide LTE coverage to at least 98 percent of the UK's population by 2017. Its network is currently open in London, Bradford, and Leeds, and it runs exclusively at 800MHz.

Vodafone switched on LTE in London today, and says it'll launch its network in another 12 cities by the end of the year, expanding to eventually cover 98 percent of the UK by 2015. It snapped up a lot of spectrum at auction, and is running its network on 800MHz and 2600MHz.

With just over 10 percent marketshare, Three is the smallest of the major carriers, and it's not ready to launch LTE yet. It plans to begin its rollout in December 2013, starting with London, Birmingham, and Manchester, and says it'll match O2's commitment to cover 98 percent of the population. It's thought that the company will run its LTE network on two frequencies: the 800MHz bands it bought at auction, and the 1800MHz spectrum it acquired from EE after the European Commission forced the larger company to drop some of its holdings.

Value

Perhaps unsurprisingly, given the long lead the company has enjoyed in LTE, EE has charged a lot for access to its 4G network. If you were to take your unlocked smartphone to EE today, they could give you a pay-monthly SIM with plans ranging from £21 for 500MB of data to £61 for 20GB.

Although neither has a plan as cheap as EE's 500MB option, both O2 and Vodafone generally offer better value than their more established competitor. O2's SIM-only plans start at £26 for 1GB, while Vodafone offers 2GB of data for the same price. Both max out with an 8GB, £36 monthly plan — for comparison, EE charges £41 for the same amount.

The dark horse in all this is Three. It's made a name for itself by giving away unlimited data on its Ultrafast (the carrier's name for DC-HSDPA, a type of 3G) network. Unlimited plans start from £15 per month, and Three has promised to not charge customers extra for LTE coverage.

Verdict

If you live in any of the UK's larger cities, you should be good for LTE coverage by now. Unfortunately, for those in rural areas, you'll just have to wait for the services to arrive. Elsewhere in Europe, Germany has taken a different route by ensuring that rural areas would be covered by LTE before big cities, incentivizing carriers to deliver LTE to everyone. In the UK, users will be stuck waiting for carriers to make good on their promises of coverage — or for O2 to fill its legal obligation. Still, for the vast majority of the UK, the solution to their LTE dilemma rests on the answers to two questions: How much data do you need? And how urgently do you need LTE speeds?

If you want a decent amount of LTE data right now — and you live in an area where it's offered — your best option is probably O2. The Telefónica-owned network has coverage in three cities and offers competitive prices, and will expand to 13 by the end of the year. If you're looking for either a tiny or a massive data allowance, EE is your best bet, with 500MB for £21 and 20GB for £61. Finally, if you're a Londoner, then Vodafone has an unmatchable 2GB plan for £26.

If, however, you don't need LTE right now, Three is almost certainly the best company for you to go to. Anticipating that it wouldn't be able to compete head-to-head with the larger networks, Three has invested massively in improving its 3G network to the point where it's now capable of delivering 20Mbps download speeds in many areas. Its unlimited data plans are unrivaled among the major carriers, as is its commitment to not levy a fee on LTE use. If waiting isn't a problem for you, then Three is the way to go.

Phil Oakley contributed to this report