Don’t forget, the iPhone 5 GSM version needs a new Nano-SIM, it will not work with your existing SIM cardIf you managed to survive this morning’s pre-order and grabbed yourself a shiny new unlocked iPhone 5 direct from Apple, you need to start thinking about SIM cards. The iPhone 5 doesn’t have the traditional, ubiquitous Nini-SIM card like the iPhone 3GS, it doesn’t even have the relatively new Micro-SIM card like the iPhone 4 either -- it uses a brand new SIM card which is called the Nano-SIM.

The Nano-SIM is much smaller than even the micro-SIM; actually it is 40 percent smaller coming in at just 12.3mm wide x 8.8mm high and 0.67mm thick. The current iPhone 4S uses a micro-SIM which measures 15mm x 12mm x 0.76mm and the 3GS uses a Mini-SIM which comes in at 25mm x 15mm x 0.76mm thick. As you can see, the SIM card has seen some huge size reductions over the last few years; it started out the size of a credit card.

So what does it mean if you have a new iPhone 5 on its way direct from Apple? Your current SIM card will not fit, you need to contact your carrier now and ask them about an iPhone 5 Nano-SIM. They should be able to send you one on time for the arrival of your iPhone 5. In the UK, my carrier Three already has them in-store and can activate it now. They provide the Nano-SIM card and SIM adaptors which will enable you to put the Nano-SIM card back in your iPhone 4S as a Micro-SIM or even your iPhone 3GS as a Mini-SIM too. This is the most reliable route as you have the Nano-SIM all ready to pop into your iPhone 5 as soon as it arrives.

Don’t forget about this or leave it too late as you may end up with a brand new iPhone 5 sitting without any service which would be extremely frustrating!

Of course if you ordered your iPhone 5 directly from your carrier, they should send out a Nano-SIM with your iPhone 5.

Latest And Best Prime Day Deals

It might be Prime Day, but this Instant Pot deal is available to everyone
Instant Pot 3-Quart Duo Mini Pressure Cooker
$39.95 $65.00 Save $25

This 3-quart multi-cooker is perfect for smaller households or serving sizes, and today's deal beats the others we've seen.

Unlock voice control with Echo device deals and $5 Amazon smart plugs
Amazon Echo devices bundled with $5 smart plugs

Amazon's Smart Plug lets you start voice controlling anything plugged into it by asking an Alexa-compatible device, and today's deal lets you snag one for only $5 with purchase of select Echo devices.

Be more productive with a year of Office 365 Home and a free $50 Amazon gift card
Office 365 Home 12-month subscription and $50 Amazon gift card
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The subscription works with up to six people, but that card can be all yours.

Amazon's Fire TV Cube is down to just $70 thanks to this Prime Day deal
Amazon Fire TV Cube
$69.99 $119.99 Save $50

Grab TCL's 32-inch 720p Roku TV for less than $100 in this Prime Day Lightning deal
TCL 32S325 32-inch 720p Roku TV
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Act fast while you can. These Lightning deals tend to sell out quick.

The Ring Alarm security system is reaching new low prices for Prime Day
Ring Alarm home security systems

Various configurations of the Ring Alarm are discounted to their best prices yet exclusively for Prime members at Amazon through Tuesday night to help keep your home secure.

The Sonos Beam Prime Day deal includes a $40 discount and 2 $50 Amazon gift cards
The Sonos Beam Prime Day deal includes a $40 discount and $100 in Amazon gift cards
$359.00 $499.00 Save $140

That's just so much savings in one deal. You'll have to wait for the physical gift cards, but that's basically $100 to spend however you want.

Prime Day dropped this PlayStation 4 console bundle to just $250
PlayStation 4 Slim 1TB console with Marvel's Spider-Man and Horizon Zero Dawn
$249.99 $359.98 Save $110

This deal on the PlayStation 4 Slim console saves you $50 off its regular price while also including Marvel's Spider-Man and Horizon Zero Dawn Complete Edition for free. You'll just need an Amazon Prime membership to snag it.

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