You can read more about the contract pricing of the iPhones here: iPhone 6 Plus release date and pricing and iPhone 6 release date and UK pricing.
iPhone buying guide: What is the best screen size for an iPhone?
There are three different screen sizes of iPhone available currently: 4-inch, 4.7-inch and 5.5-inch. That's a far cry from Apple's insistence that it wouldn't make an iPhone with a bigger screen because of "tradeoffs in screen quality", and because it is less comfortable and ergonomic to use a bigger screen. (Apple has previously emphasised the fact that the 4in screen is ideal because you can use it one-handed.)
Both of the new iPhones are larger than the 4-inch screen on last year's flagship iPhone, but Apple has made sure that the new iPhones are still comfortable to use despite the bigger surface area. For example, to compensate for the larger screen sizes, Apple's engineers have implemented a feature called Reachability. Reachability is activated by a double-touch on the Home button and it shrinks the user interface towards the bottom of the phone and closer to your thumb. This makes it easier to tap objects near the top of the screen while using one hand.
iOS 8 has also been designed to take advantage of the larger screens so, for example, the keyboard on the Plus has extra keys, including dedicated virtual buttons for cut, copy and paste. And, also on the Plus, apps like Messaging, Email, and Calendar use a split mode to show you more information.
The best screen size is likely to be a very personal thing. Perhaps you have small hands and the 5.5in iPhone 6 Plus would dwarf them. Perhaps you tend to use your iPhone most while commuting to and from work and having to use it one-handed means that even with Apple's Reachability features it would be uncomfortable to use a big screened iPhone. Or maybe you have been waiting for the bigger screen since you saw your Android wielding friends with there's and feel that at last you can enjoy the benefits of a bigger screen.
There are various apps that will benefit from the bigger screen. Maybe you primarily use your iPhone for reading articles or watching movies — the bigger screen will be ideal. If you often find yourself tapping out work related documents and emails on your iPhone the extra space — and particularly the extra keys for the keyboard will be handy. On the other hand, if you already own an iPad you may not need a bigger iPhone too.
iPhone buying guide: Which iPhone has the best display?
As we mentioned earlier, the iPhone 6 Plus has a 1920-x-1080-pixel 5.5-inch LED-backlit display offering 401 pixels per inch.
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