If portability is the key, and if you already own a tablet or use a traditional computer for everyday tasks you may not need a bigger screen iPhone.
Even if you could use a bigger screen you may not need the iPhone 6 Plus — the iPhone 6 screen is still 38 percent larger than the iPhone 5.
We think it's a shame that Apple is only offering new iPhones in these bigger sizes, we hope that in the future the company will upgrade the smaller 4in iPhones. Perhaps an iPhone 7 mini could arrive next year.
iPhone buying guide: iPhone colour choices
The iPhone 6, iPhone 6 Plus and the iPhone 5s all offer the same colour choices: silver (white), gold and space grey (black).
Only the iPhone 5c comes in bright colour choices. Choose from white, pink, yellow, blue and green.
Of course the colour choice may be redundant if you choose to put your iPhone in a case as many do, in order to protect them.
We have a round up of iPhone 6 and iPhone 6 Plus cases here: Best cases for iPhone 6: 14 iPhone 6, iPhone 6 Plus cases
iPhone buying guide: Which iPhone is best for software?
iOS 8 works on the latest iPhones including the iPhone 5s, 5c, 5 and iPhone 4s as well as the new iPhone 6 and iPhone 6 Plus (obviously).
There are various features coming in iOS 8 that enhance existing iPhones as well as the new iPhones, particularly Continuity, Widgets, new tools in Mail and Messages, the new keyboard features.
If you're excited by iOS 8 but you're willing to sacrifice a few features the iPhone 4s might be ok, but you need to keep in mind that that phone will be able to utilise many of the new features to their full potential and installing the new software may render your phone slower and less responsive. (Read about why Apple isn't making your iPhone slower on purpose)
It can be a whole lot worse than the iPhone 4s software situation though. Many of the features that came with iOS 6 back in 2012 don't even work with the iPhone 4. The main things missing are Siri, FaceTime over 3G, Flyover and turn-by-turn navigation. That phone won't even run iOS 8.
You can also expect some of the older iPhones not to offer support for newer apps. Developers had been focusing efforts on four-inch iPhones,we expect that they will now focus their attention on the screen size of the new iPhones.
iOS 9 is coming soon, though. We're expecting to get our first glimpse at the new operating system on 8 June at Apple's WWDC 2015 conference. We don't know what new features we'll be getting yet, but you can expect that not all of them will work on Apple's older iPhones, so it might be time to think about upgrading when it gets released to the public in September. Find out more in our iOS 9 release date rumours article.
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