The iPod touch is the cheapest full-iOS device and boasts many iPhone 4 features at a fraction of the price. It's got the sharp Retina display, fast A4 processor, FaceTime video calling, can record HD video, and connects to Wi-Fi networks. For web browsing, listening to music and shooting video, it's on a par with the iPhone 4.
However, the iPod touch won't connect you direct to a mobile network. This means you can't make a regular calls and can only access the web over Wi-Fi. But once you've bought an iPod touch, there's no contract or regular top-ups to pay for at all. And by using apps such as Skype, you can still make calls over Wifi.
The iPhone 4 is arguably the ultimate mobile. It does everything the iPod touch does, but it has a better rear-facing camera and the Retina display features in-Plane Switching (for improved viewing angles). Yes, there's the antenna issue, but a case solves this. You will be shelling out on a contract or PAYG top-ups for as long as you want to use the phone, though.
Remember that the 8GB iPhone 3GS is still available, and it's a very able performer. It tuns iOS 4 well (and will run iOS 5), but lacks the Retina display and FaceTime calling (since there's no front-camera). The battery life and the rear-facing camera are inferior, too. However, it remains an impressive product.
Then there's the iPad 2. You have the choice of Wi-Fi only or you can pay more for a model including 3G mobile connectivity. Both have a dual-core A5 processor, a 9.7-inch screen, front-and-rear-facing FaceTime cameras and phenomenal battery life.
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