Before we start, here's a quick iPhone history to put Apple's smartphone in context.
The first iPhone launched in 2007. Apple actually unveiled it in January 2007, but it didn't launch until the end of June in the US, and November in the UK. The first ever iPhone didn't even offer 3G and it wasn't even the first smartphone, but it did reinvent smartphones and pretty soon after all the other mobile manufacturers started producing iPhone-like handsets with touchscreens and apps just like Apple's iPhone.
Apple has introduced a new iPhone (or two new iPhones) every year since 2007. The company has also updated the iPhone operating system — iOS — every year around the time the new iPhone launches. This means that anyone who owns an iPhone (or iPad) can update their device and enjoy many of the new features offered by the newest handsets.
iPhone buying guide: The full iPhone range (and which iPhone have you got?)
First things first. If you already own an iPhone, which iPhone do you have? This is an important question. If you already own an iPhone it is likely to influence your decision of which iPhone to purchase next. And if you have never owned an iPhone, your needs may be influenced by the Android or Windows smartphone that you have been using.
The iPhone models available currently are as follows:
iPhone 6 Plus
The new iPhone 6 Plus is Apple's first phablet-style phone. Phablet is basically the name used for phones that are so big that they are like small tablets. The iPhone 6 Plus has a 5.5-inch screen so it's not a lot smaller than the iPad mini. In addition to the bigger, better screen the Plus offers a better camera than the iPhone 6. Read our iPhone 6 Plus review.
iPhone buying guide: iPhone 6 Plus
Who is the iPhone 6 Plus best for? Those who want a 'phablet' experience — one which is midway between a phone and a small tablet. Big fans of gaming and movies, both of which look great on the 6 Plus's big screen. Some business users may find that the big screen is good for productivity apps. Early adopters and others who like to have the latest thing. Those on a big budget.
If you've got an iPhone 6 Plus... Then you're on the top-tier iPhone, so there's no need to upgrade! Of course, if you're finding the device a bit too big (and more than a few buyers have found this), then you might choose to downgrade to the smaller iPhone 6 or the still-smaller iPhone 5s.
The iPhone 6 has a bigger screen than the iPhone 5s: 4.7 inches (measured diagonally, corner to corner) compared to 4 inches. It's also thinner and lighter than the previous year's model, and like the iPhone 6 Plus it features a better A8 processor and an NFC chip for mobile payments. Read our iPhone 6 review and our iPhone 6 vs iPhone 6 Plus comparison review.
Sign up for Computerworld eNewsletters.