Wondering whether to upgrade your iPhone and which new iPhone to choose? Here are our answers to some of your questions about Apple's two new smartphones: the iPhone 5s and iPhone 5c. Wondering whether to buy a Samsung Galaxy S5? Read our comparison review of the iPhone 5s and Galaxy S5. Also: read our article on whether to wait for the iPhone 6.

How much do the new iPhones cost?

In the run up to Apple's launch of the iPhone 5c and iPhone 5s the rumours suggested that the iPhone 5c would be a cheaper iPhone, but the price difference was really minimal. Initially the off contract price of the iPhone 5c wasn't much cheaper than the iPhone 5 was last year when it launched. A 16GB iPhone 5c costs £469 while the 16GB iPhone 5 was £529.

Perhaps in response to poor sales of the iPhone 5c, Apple has now introduced a lower-priced iPhone 5c. The 8GB iPhone 5c costs £429. This places its price at £100 less than the iPhone 5 was when it launched last year.

Even with this slighly cheaper iPhone 5c there's not really much difference between the price of the iPhone 5c compared to the iPhone 5s. At £429 it costs £120 less than the entry-level iPhone 5s, which includes twice as much memory and many other features.

However, the price difference between the 16GB iPhone 5c and 16GB iPhone 5s is so minmal that it is hardly surprising that more people have reportedly opted for the iPhone 5s. The 16GB iPhone 5c is £469. Pay just £80 more and you can get a 16GB iPhone 5S for £549.

If you want the 32GB iPhone 5c, the price is the same as for the 16GB iPhone 5s, which is £549.

The 32GB iPhone 5s is £629 and the 64GB iPhone 5s is £709.

Wondering why Apple's iPhone 5c isn't cheap? Read our article: Why Apple didn't launch a low-cost iPhone 5c. However, it is generally agreed that Apple made a mistake by pricing the iPhone 5c so high, the sales of that iPhone were much lower than Apple had anticipated, with the iPhone 5s proving to be the more popular option. It seems likely that Apple has introduced a lower-cost iPhone 5c in reaction to this. Many have complained that the price is still too high, especially in comparison to low-cost phones offered by other smartphone manufacturers. As our colleague Jim Martin on PC Advisor said: "Why not buy three Motorola G smartphones instead."

If you want to pay your cash up front, you will be able to grab yourself an iPhone 5c or an iPhone 5s without a contract (aka unlocked) from Apple’s online store, from its physical stores and, of course, from mobile phone stores like Carphone Warehouse. Some people who have an existing contract that they don't want to lose, or those who prefer the pay-as-you go model may choose to do this.

Buying an iPhone 5c with a mobile contract is a more complicated business thanks to the huge variation tariffs and networks on offer. The networks are likely to continue to try and undercut each other on pricing.

O2 already offers a £0 upfront 8GB iPhone 5c for £43 a month.

We've outlined the tariff deals we've had confirmation of so far in these articles:

iPhone 5s tariffs and pricing: how much does Apple's iPhone 5s cost on UK contract?

iPhone 5c pricing and tariffs: how much does Apple's iPhone 5c cost on UK contract?

What are the colour options for the new iPhones?

The most striking difference between the iPhone 5s and iPhone 5c is colour. These new iPhones mark the first time the iPhone has comes in anything other than black and white.

iPhone 5c colours

The iPhone 5c is available in pink, yellow, blue, green, or white. The colours are bright and vibrant. According to a Macworld poll, the most popular colour for the iPhone 5c is blue (43% of the vote).

iPhone 5s colours

The iPhone 5s looks a little more like the iPhone 5, but there is a new colour option: gold, along with silver and gray (or Space Gray as Apple is calling it). The silver is comparable to 2012's White & Silver option, and the Space Gray reminds us of the Black & Slate iPhone 5 option in 2012. The gold isn't as 'blingy' as we expected and has proven to be popular, although the Space Grey option is said to be the most popular.

How big are the new iPhones?

Both the iPhone 5s and the iPhone 5c have a 4in Retina display. However the dimensions and weight of the two phones are slightly different.

The iPhone 5c measures 124.4mm by 59.2mm, and is 8.97mm deep. It weighs 132 grams.

The iPhone 5s measures 123.8mm by 58.6mm, and is 7.6mm deep. It weighs 112 grams.

This means the iPhone 5c is slightly longer and thicker than the iPhone 5s, and a little heavier.

The iPhone 5 measurements were identical to the iPhone 5s - 123.8mm by 58.6mm and the depth was 7.6mm - so you may find that your existing iPhone 5 cases are compatible with the iPhone 5c.

Both phones are a lot lighter than the iPhone 4s (which is still available). The iPhone 4s weighs in at 140 grams.

Will the new iPhones work with 4G?

The iPhone 5c and iPhone 5s will support more LTE 4G bands than any other smartphone in the world, according to Apple. That's support for up to 13 LTE wireless bands. Initially there was some concern when the information page on Apple's website suggested that only EE and Vodafone would be able to provide 4G, however nearly all the networks are offering the iPhone 5c and iPhone 5s on their 4G network (except for T-Mobile and 3 at present).

The iPhone 5S and iPhone 5C will run on the following bands, in the following MHz according to Apple's notes: 1 (2100 MHz); 2 (1900 MHz); 3 (1800 MHz); 5 (850 MHz); 7 (2600 MHz); 8 (900 MHz); 20 (800 DD). 

How do the cameras compare?

iPhone 5s camera

The iPhone 5s camera uses a new, five-element lens that Apple designed specifically for the new iPhone. This new lens offers an f/2.2 aperture, the sensor has a 15 per cent larger active area, and the pixels on this sensor are 1.5 microns in size, larger than the iPhone 5 and larger than other smartphones. The iPhone 5s also includes a new dual-LED True Tone flash that Apple says is the first of its kind on a phone or a standalone camera. One flash is cooler white, while the other is amber with a warmer color temperature. The phone monitors ambient light and then fires the two flashes together to match that light. Together, Apple says, the two flashes provide more than 1000 unique light combinations, for flash lighting that’s brighter and more natural. The 5s also includes improved image stabilization features, a new burst mode and slow-motion video recording.

A recent update to the iPhone 5s camera in iOS 7.1 has seen it gain a new HDR-Auto feature that automatically uses HDR if it feels that the photograph will benefit from it.

iPhone 5c camera

Like the iPhone 5s, and like the iPhone 5 before it, the iPhone 5c offers an 8MP camera. However, this 8MP camera is inferior to the camera in the iPhone 5s which offers an f/2.2 aperture.

Read our full iPhone photo comparison in our test.

Is battery life in the iPhone 5s and iPhone 5c any good?

Apple claims that both the iPhone 5s and iPhone 5c offer battery life equal to or greater than that of the iPhone 5. Specifically, the company says the new iPhones offer 10 hours of 3G talk time, 10 hours of LTE or Wi-Fi browsing, or 250 hours of standby time. Compare that to Apple’s claims for the iPhone 5 when that model was released: 8 hours of 3G talk time, 10 hours of Wi-Fi browsing, or 225 hours of standby time.

What storage options are available?

There are now three versions of the iPhone 5c available: 8GB, 16GB and 32GB. The 8GB version was introduced on 18 March 2014.

While some have criticised Apple for offering an 8GB version, suggesting that it isn't sufficient for the needs of smartphone users, it should be noted that at least with the 8GB iPhone 5c you will get almost 8GB of usable space. Samsung's 16GB Galaxy S5 actually only offers 7.86GB storage to users because the operating system and included apps take up so much space on the device.

As for whether 8GB is enough, J. Gold Associates analyst Jack Gold has said: "At the lower end of the markt, most people aren't coming close to filling up 8GB".

The iPhone 5s is available in 16GB, 32GB and 64GB versions. There had been some expectation that Apple might offer a 128GB version of the iPhone, but the company launched no such product.

For many the extra storage offered by the iPhone 5s will be the deal breaker. However, with iCloud, and the potential offered by external storage devices, you may not need as much storage as you think.  

For many the small saving of £40 between the iPhone 5c with 16GB and the iPhone 5c with 8GB will not be enough to justify the loss of storage space. While it's true that just a few years ago a 8GB iPhone was sufficient, these days most people will find that they fill up the memory on their device very quickly, and since there is no way to add additional storage other than by purchasing a separate Wi-Fi storage device, it isn't going to appeal to some.

What about the iPhone 4s?

Apple's still offering the iPhone 4s. You may be wondering whether it's a good option for your needs. Read this article for more information: Should I buy an iPhone 6 or buy an iPhone 5s or iPhone 5c? 

How does the iPhone 5s compare to the competition?

There are several rumoured iPhone 5s features that Apple didn't show off at its iPhone event, some of which feature in smartphone rivals from Apple's competitors. Read this article for more information: iPhone 5s vs competition: 8 features Apple's new iPhone 5s doesn't have. Plus: Here's our reaction to the new phones released at Mobile World Congress.

Read our iPhone 5S vs iPhone 5C comparison review: what's the difference between the new iPhones

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