The long-awaited iPhone 5 was finally revealed in a blaze of publicity last week, and is already predicted to become the biggest selling smartphone of all time.

With more than 2 million pre-orders placed in the first 24 hours, Apple are already warning that demand is outstripping supply and that many of the orders wouldn’t be shipped until October.

Regardless, the handset is likely to smash the records set by its predecessor, the iPhone 4s, with global sales of over 50 million by the end of the year being mooted.

Hard core fans have already begun queuing outside Apple stores in a bid to be among the first to get their hands on the must-have gadget for 2012, despite the whopping £529 ‘unlocked’ price tag.

UK mobile networks are taking pre-orders for phones that come with a pay-monthly contract, allowing consumers to get the handset at a significant discount – albeit with a hefty monthly commitment on top.

Even if you can afford the up-front cost, can stomach paying out £36 or more a month, and manage to navigate the fight for available stock, there’s one more potential hurdle before you can get your hands on an iPhone 5 - your credit rating.

Given that mobile networks subsidise the cost of the handset (hence the high monthly line rental), they stand to lose a lot of money should a customer default on their contract. This is especially true for top-end handsets such as the iPhone. As a result, customers who get a snazzy phone free with their contract are subject to credit checks before being able to get their hands on it.

Any evidence of problems paying previous credit agreements could see the application turned down flat, especially if the late payments were against another mobile contract.

As with other credit agreements such as credit cards and loans, each provider will have their own acceptance criteria, and won’t give you the exact reason if you are declined.

Even if you manage to get approved, previous credit problems might see you asked to pay an additional deposit or have a spend limit applied to your account.

Given the clamour to own the latest handset as soon as it is available, being turned down for credit would be a major disappointment for most people – especially if they didn’t really know why. That’s why it’s so important to be aware of the information that is held about you and used to make these decisions.

And if all else fails, you’ll have at least a year to try and improve your credit rating in time for the iPhone 6…