Best O2 phones

O2 first grabbed the attention of many mobile-phone fans back when it had the exclusive rights to the iPhone. Those days are over but it's still the only network to offer visual voicemail on the iPhone 4.

There's more to O2 than Apple's handset anyway. We've picked our favourite phones on the network in our round-up below.  

Unfortunately, the generous data allowance that powered adoption of the iPhone and other smart phones is no more. O2 cut its 'unlimited' data bundles back in 2010. The operator hopes to tempt us instead with a medley of special offers, such as a pre-paid debit card called O2 Money, and discounts through its O2 Priority Moments voucher app.

Still, none of these temptations represent a killer reason to pick O2 over another network, so you should be sure to compare prices before getting stuck into O2's extras. Before switching to O2, you should also make sure that you can get a signal by using its online coverage checker. 

When it comes to customer service, O2 shines. A customer satisfaction survey by Which? magazine ranked the network second only to Tesco for customer satisfaction among contract customers. Among pay as you go peeps, O2 was pipped by Asda and Tesco, but still came out above the rest of the major networks.

O2 also tops Ofcom's data, with the lowest number of customer complaints of all networks by a significant margin.

We also high-five O2 for its website. Unlike the dismal, confusing efforts of Vodafone and Orange, O2's site tends to be clear and usable. There's even a page where you can ask for your phone to be unlocked, rather than having to navigate the support-line hell maze.